Added colour picker function to viewer

Added the method get_colour to the Viewer object. Returns a hsv
which can be passed into binary region finder. Wrote tests for the
new method. Also updated the readme file with some notes on how to use the
viewer.
Merge with master
Merge pull request #30 from tonysimpson/replay

Replay
Merge with master
What idiot thought logging was needed in tests? (Also fixes import annoyances)
Ensure replay tests are included, pep8 fixes
Skip bad test
Ignore test log files
Merge pull request #31 from ant1441/test-rework

Test rework
Another merge with master, thanks Adam
Fixed lingering logger
Removed use of pkg_resources in test_viewer
Added matplotlib as a dependency
Syntax error
Remove logger import
Update README.md
Added missing return
Merge branch 'colour_picker' of https://github.com/thetestpeople/Geist into colour_picker
Fix repo location
Mark code as python