Replace "memoize" decorator with "functools.lru_cache".

Closes #107.
Fix incorrect hue quadrature computation in "CIECAM02" colour appearance model.
Improve consistency in colour appearance models specification attribute names and order.

Closes #82.
Merge branch 'feature/CAMs' into develop
Add "CONTRIBUTING.rst" document.
Update documentation directory structure.
Update ".travis.yml" file.
Update various docstrings.
Update various ".rst" files.
Update ".travis.yml" file.
Programmatically round "LLAB(l:c)" colour appearance model normalised cone responses to "CIE XYZ" colourspace matrix.
Add docstrings to CAMs matrices.
Update various docstrings.
Fix regression on boundaries computation in "colour.SpectralPowerDistribution.interpolate" method.
Fix incorrect domain reported for tristimulus values computations.
Update various plotting objects.
Add special contributor.
Add convenient shell verbose message box for examples.
Remove visual noise in API toctree.
Reduce left padding of API toctree.