Refactored LDA module (first working version).
Added LabelEncoder and updated most of the docstrings
Updated more docstrings
Return self in fit()
Use equal priors by default
Added simple LDA example
Moved some common code into helper function
Support manually set shrinkage parameter (alpha)
For now only the svd solver supports the transform method
Updated LDA unit tests
Simplified LDA vs. shrinkage LDA example
Removed magic number
Addressed @mblondel's comments
Updated parameter name in help text
Parameters are now consistently named; also refactored the _means_cov() function
Added different shrinkage values to test cases
Updated LDA example and removed decision plane comparison
Increased coverage
PEP8 style conventions
Catch NotImplementedError