Added more example cocktails
Updated smiles
Removed dependency on RDKit.
Major refactoring.

- Removed c6 specific functions
- Removed custom json serialization
- Added marshmallow Serialization
- Modified summary function to only add mw and density
- Added internal_sim and distance functions to screen module
Change default weights to floats
Refactored cli to use click
Updated docs
Removed old cli script
Updated docs for new cli
Fix json serialization to output null values
Removed utf-8 conversion of smiles strings
Re-generated screens
Updated changelog
Updated install docs
Added crystal hits data
Updated depenedencies