Update guava to 11.0.1 - match the version used by git-plugin

The latest guava version (16.0) causes test failures, so cannot be
used yet.  This version is consistent with the version used by
git-plugin which may avoid silent incompatibilities between the two
plugins.
[JENKINS-20445] [JENKINS-20387] [JENKINS-20750]
Expose timeout for clone and fetch command when using CliGit
Add bare option to GitAPITestCase init method, use to simplify test_push

The test_push fails on Red Hat Linux 6 because Git 1.7.1 version
behaves different than more recent versions.  Git 1.7.1 reports "You
are on a branch yet to be born" when attempting to checkout a branch
from a freshly initialized git repository.  Checkout of a new branch
on an empty repository is quite a corner case, and there is little
motivation to fix that, since later git versions do not show the same
problem.

Switching test_push to push to a bare repository seems more likely as
a scenario for push testing anywway, since most writers agree that
pushing to a working repository has several problems.
Fix form validation for HTTP-based Git repos by creating a temporary workspace
using the same directory used to store the credentials.
Merge pull request #100 from rogerhu/fix_git_repo_errors_2

Fix HTTP-based credentials issues during form validation.
Merge pull request #99 from MarkEWaite/master-fix-test_push_RH6

Add bare option to GitAPITestCase init method, use to simplify test_push
Merge pull request #87 from MarkEWaite/master-update-guava-to-match-git-plugin

Update guava to 11.0.1 - match the version used by git-plugin
Merge pull request #92 from wannessels/master

[JENKINS-20445] [JENKINS-20387] [JENKINS-20750]