Merge pull request #76 from cogmission/encoderwork

Encoderwork - Phase 1 (Base encoder class and ScalarEncoder)
Make encoder library stateful
Merge pull request #78 from cogmission/statefulencoder

Make encoder library stateful
regenerate docs for new api changes
Merge pull request #80 from cogmission/statefulencoder

regenerate docs for new api changes
Merge pull request #81 from cogmission/categoryencoderwork

new docs