* : Setup testing and implemented tests for tokeniser class methods
tokeniser_test.py : Added more automated tests
tests/test_tokeniser.py : Added more tests and renamed from 'tokeniser_test'
test_tokeniser.py : Removed unnecesary import statements
Merge branch 'commands'

Changes to commands, including new features, which will need to be
branched for distribution at a later date
* : Started implementing line number bar for editor
* : Extrancted rendering functionality from viewer to seperate 'renderer.py' file
* : Readability refactoring
renderer.py : Fixed issue with repeat action not working as expected
* : OS X Distribution test
* : Removing test dist files
* : Removing unused code
* : refactoring
editor.py : refactoring dimensions
* : Added mouse coordinates labels
about_window.py : Updated
* : Modified animation speed slider to be more intuitive
* : Restructured 'more controls' secion of the GUI
* : Restructured 'core controls' secion of the GUI
gui.py : Disabled window resizing for main window