Support Adding and Removing of branches and tags
This commit adds support to create and remove branches and tags from gitlab-shell.

The code style was followed as closely as possible to the original.

The purpose of this commit is that I will be adding support to the Gitlabhq (Gitlab) project
in order to allow adding and removing of branches and tags through their API.
Adding tests for the addition of create-branch, create-tag, rm-branch, rm-tag

The previous commit has the code addition to support adding and removing branches and
tags in a repository - This commit ensures basic test cases are supported.
Merge pull request #69 from thomasbiddle/support_adding_and_removing_branches_and_tags

Support adding and removing branches and tags