Updated readme.  Finished Dataset.extract_component.  Added some planning.
Added a TextLengthBinner class to bin a word count of a body of text. Added a clean_row function to Dataset since the previous approach breaks when we have a non-empty string of text
Merge pull request #1 from samurain/nlp

Added a TextLengthBinner class to bin a word count given a body of text. Added a clean_row function to Dataset since the previous approach breaks when we have a non-empty string of text.
Added Dataset.save_as_occam3_format function to let data be exported into Occam3.
Split out data function into new file.

Split out data functions in to new (Data.py) file.  Required breaking a
used-but-not-needed dependency from Dataset to Variable and extracting
the needed info from the dataset itself.  Also made a bit of progress on
figuring out how I intend to structure the Component and Model classes.
Finished Component and ComponentWithData.

Component now has __str__ and return_df functions.  ComponentWithData
now has return_entropy function.
Added Model infrastructure, Updated style.

Added Model and ModelWithData infrastructure.  Added Binner base class.
Updated to new style classes.
Model development.  Cleaned a bit.

Added Model __str__ tests.  Cleaned comments.  Added .gitignore.
Pulled component frequency tables into MWD init.

Pulled component frequency into ModelWithData.__init__().