Merge pull request #116 from guilhermef/master

More GetTree tests
Adding install instructions for homebrew
Merge pull request #118 from ricardodani/patch-1

Adding install instructions for homebrew
contributors: added Ricardo L. Dani.
Simplify parameters passing, no need to unpack (re #119)
Allow empty message (no content) when committing
Merge pull request #119 from scorphus/empty-content

Allow empty message (no content) when committing
Remove blank lines in compliance with project's standards
Implement methods to get branches in a repository (re #120 and #123)

Add a new mock method to create branches on an existing repo
Merge pull request #124 from scorphus/get-branches

Implement methods to get branches in a repository (re #120 and #123)
Repository: Improved GetForEachRef

Removed unnecessary replace
Merge pull request #125 from marcelometal/improve_get_for_each_for

Repository: Improved GetForEachRef
Fix error message, make it generic
Improve mock/tests for GetBranch (re #123)
Add test for subject with tab (re #123)
Test GetForEachRef method instead of the one that uses it
Warily treat an empty or invalid pattern (re #120 and #123)
Merge pull request #127 from scorphus/test-get-for-each-ref

Warily treat empty or invalid pattern (re #120 and #123)
Correctly accept an empty pattern (re #120 and #123)
Improve GetForEachRef() tests (re #120 and #123)