A good starting point for ~/.gitconfig

.gitconfig

# -*- Conf -*-
[color]
	branch = auto
	diff = auto
	status = auto
        showbranch = auto
	ui = true

# color.branch
#     A boolean to enable/disable color in the output of git-branch(1). May be set to always, false (or
#     never) or auto (or true), in which case colors are used only when the output is to a terminal.
#     Defaults to false.

# color.interactive
#     When set to always, always use colors for interactive prompts and displays (such as those used by
#     "git-add --interactive"). When false (or never), never. When set to true or auto, use colors only
#     when the output is to the terminal. Defaults to false.

# color.diff
#     Whether to use ANSI escape sequences to add color to patches. If this is set to always, git-
#     diff(1), git-log(1), and git-show(1) will use color for all patches. If it is set to true or
#     auto, those commands will only use color when output is to the terminal. Defaults to false.

#     This does not affect git-format-patch(1) nor the git-diff-* plumbing commands. Can be overridden
#     on the command line with the --color[=<when>] option.

# color.pager
#     A boolean to enable/disable colored output when the pager is in use (default is true).

# color.showbranch
#     A boolean to enable/disable color in the output of git-show-branch(1). May be set to always,
#     false (or never) or auto (or true), in which case colors are used only when the output is to a
#     terminal. Defaults to false.

# color.status
#     A boolean to enable/disable color in the output of git-status(1). May be set to always, false (or
#     never) or auto (or true), in which case colors are used only when the output is to a terminal.
#     Defaults to false.

# color.ui
#     This variable determines the default value for variables such as color.diff and color.grep that
#     control the use of color per command family. Its scope will expand as more commands learn
#     configuration to set a default for the --color option. Set it to always if you want all output
#     not intended for machine consumption to use color, to true or auto if you want such output to use
#     color when written to the terminal, or to false or never if you prefer git commands not to use
#     color unless enabled explicitly with some other configuration or the --color option.


# color.branch.<slot>
#     Use customized color for branch coloration.  <slot> is one of current (the current branch), local
#     (a local branch), remote (a remote-tracking branch in refs/remotes/), plain (other refs).

#     The value for these configuration variables is a list of colors (at most two) and attributes (at
#     most one), separated by spaces. The colors accepted are:
#       normal, black, red, green, yellow, blue, magenta, cyan and white;
#     the attributes are:
#       bold, dim, ul, blink and reverse.
#
#     The first color given is the foreground; the second is the background.
#     The position of the attribute, if any, doesn't matter.

[color "branch"]
	current = yellow reverse
	local = yellow
	remote = green

# color.diff.<slot>
#     Use customized color for diff colorization.  <slot> specifies which part of the patch to use the
#     specified color, and is one of plain (context text), meta (metainformation), frag (hunk header),
#     func (function in hunk header), old (removed lines), new (added lines), commit (commit headers),
#     or whitespace (highlighting whitespace errors). The values of these variables may be specified as
#     in color.branch.<slot>.

[color "diff"]
	meta = yellow bold
	frag = magenta bold
	old = red bold
	new = green bold

# color.decorate.<slot>
#     Use customized color for git log --decorate output.  <slot> is one of branch, remoteBranch, tag,
#     stash or HEAD for local branches, remote-tracking branches, tags, stash and HEAD, respectively.

# color.interactive.<slot>
#     Use customized color for git add --interactive output.  <slot> may be prompt, header, help or
#     error, for four distinct types of normal output from interactive commands. The values of these
#     variables may be specified as in color.branch.<slot>.

# color.status.<slot>
#     Use customized color for status colorization.  <slot> is one of header (the header text of the
#     status message), added or updated (files which are added but not committed), changed (files which
#     are changed but not added in the index), untracked (files which are not tracked by git), branch
#     (the current branch), or nobranch (the color the no branch warning is shown in, defaulting to
#     red). The values of these variables may be specified as in color.branch.<slot>.

[color "status"]
	added = yellow
	changed = green
	untracked = cyan

[core]
	whitespace=fix,-indent-with-non-tab,trailing-space,cr-at-eol
        excludesfile = ~/.gitignore-rab
[apply]
	whitespace = nowarn
[branch]
	autosetuprebase = always
[rerere]
	enabled = 1
[log]
        date = short
        # date = relative
[alias]
	st = status -sb
	ci = commit
	co = checkout
        graph = log --graph --oneline --decorate=short --branches='*'
	br = branch
	df = diff --color-words='[^[:space:]]'
	sh = show --color-words='[^[:space:]]'
	lg = log -p
        serve = !git daemon --reuseaddr --verbose --base-path=. --export-all ./.git
        pend = cherry -v origin/master
#	prefab = cherry -v origin/fabrication
[format]
        pretty = '%C(yellow)%h%Creset %C(magenta)%cd%Creset %d %s'
[user]
#	name = 
#	email = 
[github]
#	user = 
[gitjour]
#	prefix = 

#For merge conflict resolution: https://gist.github.com/643979
#
# ===> .git/info/attributes  (or ~/.gitattributes)
# Gemfile.lock merge=bundleinstall
# db/schema.rb merge=railsschema
#
# ===> .git/config           (or ~/.gitconfig)
# [merge "bundleinstall"]
#   name = bundle install
#   driver = bundle install
# [merge "railsschema"]
# 	name = newer Rails schema version
# 	driver = "ruby -e '\n\
# 		system %(git), %(merge-file), %(--marker-size=%L), %(%A), %(%O), %(%B)\n\
# 		b = File.read(%(%A))\n\
# 		b.sub!(/^<+ .*\\nActiveRecord::Schema\\.define.:version => (\\d+). do\\n=+\\nActiveRecord::Schema\\.define.:version => (\\d+). do\\n>+ .*/) do\n\
# 		  %(ActiveRecord::Schema.define(:version => #{[$1, $2].max}) do)\n\
# 		end\n\
# 		File.open(%(%A), %(w)) {|f| f.write(b)}\n\
# 		exit 1 if b.include?(%(<)*%L)'"
#== but the %L (set to 7) and the --marker-size option seem to not work. This looks for <<<<<<< ('<'*7)
# [merge "railsschema"]
# 	name = newer Rails schema version
# 	driver = "ruby -e '\n\
# 		system %(git), %(merge-file), %(%A), %(%O), %(%B)\n\
# 		b = File.read(%(%A))\n\
# 		b.sub!(/^<+ .*\\nActiveRecord::Schema\\.define.:version => (\\d+). do\\n=+\\nActiveRecord::Schema\\.define.:version => (\\d+). do\\n>+ .*/) do\n\
# 		  %(ActiveRecord::Schema.define(:version => #{[$1, $2].max}) do)\n\
# 		end\n\
# 		File.open(%(%A), %(w)) {|f| f.write(b)}\n\
# 		exit 1 if b.include?(%(<)*7)'"
[push]
	default = simple

fix option in core.whitespace is not doing anything - see nodejs/node#11412 for a similar bug report