V2 Branch

[SeanNaren]

There are a few issues I'll be addressing in this branch:

• [x] Fix current branch; it does not converge as a few commits before
• [x] Convert AN4Train/AN4Test to use cmd to input arguments, create bash scripts to run these
• [x] Expose parameters of DeepSpeechModel to allow easier customisation
• [x] Revise current flow of objects such as Evaluator and Model Evaluator
• [x] Add training graph with CER/WER
• [x] Add example prediction script
• [x] Add WER/CER results in README