Updated to VS 2013

.gitconfig

[diff]
         tool = vsdiffmerge
         guitool = vsdiffmerge
[difftool]
         prompt = true
[difftool "vsdiffmerge"]
         cmd = \"C:/Program Files (x86)/Microsoft Visual Studio 12.0/Common7/IDE/vsdiffmerge.exe\" \"$LOCAL\" \"$REMOTE\" /t
         keepbackup = false
         trustexistcode = true
[merge]
         tool = vsdiffmerge
[mergetool]
         prompt = true
[mergetool "vsdiffmerge"]
         cmd = \"C:/Program Files (x86)/Microsoft Visual Studio 12.0/Common7/IDE/vsdiffmerge.exe\" \"$REMOTE\" \"$LOCAL\" \"$BASE\" \"$MERGED\" /m
         keepbackup = false
         trustexistcode = true