Add JaCoCo code coverage reporting
Add tests of addRemoteUrl, getRemoteUrl, and setRemoteUrl methods
Add tests of checkout(String, String) method

Used the git-client-1.6.0 SHA1 in one of the tests and cloned the local
mirror of the git client repo so that a consistent value is available.
Add revList tests - local branch, remote branch, and tag
Add test of deprecated getRemoteUrl(String, String)

Fails on JGit implementation because the JGit implementation returns
an empty string while the CGit implementation returns the expected
value.
Add test of deprecated merge(String) method
Add test of changelog(String, String) method
Merge pull request #58 from MarkEWaite/master-add-deprecated-merge-test

Add test of deprecated merge(String) method
Merge pull request #52 from MarkEWaite/master-coverage

Add JaCoCo code coverage reporting
Merge pull request #54 from MarkEWaite/master-add-checkout-tests

Add tests of checkout(String, String) method
Merge pull request #55 from MarkEWaite/master-add-remoteUrl-tests

Add tests of addRemoteUrl, getRemoteUrl, and setRemoteUrl methods
Merge pull request #57 from MarkEWaite/master-add-deprecated-getRemoteUrl-test

Add test of deprecated getRemoteUrl(String, String)
Merge pull request #59 from MarkEWaite/master-add-changelog-bounded-test

Add test of changelog(String, String) method
Merge pull request #56 from MarkEWaite/master-add-revList-tests

Add revList tests - local branch, remote branch, and tag
Merge remote-tracking branch 'upstream/master' into JENKINS-19994-cannot-delete-jgit-workspace