Update for ruby.nanorc to support Vagrantfile with syntax highlighting

ruby.nanorc.diff

diff --git a/ruby.nanorc b/ruby.nanorc
index b30b229..3bdfd81 100644
--- a/ruby.nanorc
+++ b/ruby.nanorc
@@ -1,6 +1,6 @@
 ## Here is an example for Ruby.
 ##
-syntax "ruby" "\.rb$"
+syntax "ruby" "Vagrantfile|\.rb$"
 header "^#!.*/ruby[-0-9._]*"
 ## Asciibetical list of reserved words
 color yellow "\<(BEGIN|END|alias|and|begin|break|case|class|def|defined\?|do|else|elsif|end|ensure|false|for|if|in|module|next|nil|not|or|redo|rescue|retry|return|self|super|then|true|undef|unless|until|when|while|yield)\>"