rename methods

Merge pull request #27 from kongrongx/patch-2

Update ddqn.py

Merge pull request #19 from pskrunner14/master

moves batch update logic to dqn_batch.py

changes lin to quad

ref comments

remove redundant files

fixes huber loss def

fixes replay loss return error

updates huber loss function

updates huber loss function

implements training on batches

implements training on batches

fix dqn and ddqn