Retrieve remote pushurl independently of user's locale

git-review tried to parse the output of "git remote show -n" to
retrieve a remote's pushurl and failed if the user's locale was not
English.  This change reads the configuration directly instead.

Change-Id: Idbf98ae00538dd611277ca862da969f22cbe6265
Closes-Bug: #1177429
Merge "Retrieve remote pushurl independently of user's locale"