push failure on domain-connected machine

[Erik Blake <erik@icefield.yk.ca>]

When pushing an existing local repo to a new remote repo, git 2.6.3
misidentifies the user's home directory on a domain-connected Windows
machine. My machine is running Win7-64 and I have tried both the 32-bit
and 64-bit version of git.

For example, the following sequence fails on the last command:

>git remote add remote <remote repo URL>
>git config remote.uf.push refs/heads/master:refs/heads/master
>git push remote master

The error returned by the last command is "Could not create directory
'/home/foo/.ssh'."

git should be targeting the directory '/home/foo.domain/.ssh' instead.

The path to the user profile should be taken from %HOMEDRIVE%%HOMEPATH%
or, preferably, %USERPROFILE% and not %USERNAME%, unless %USERDOMAIN% is
appended when a domain-connected computer is detected.

git 1.9.5 does not exhibit this problem.