v0.7.0

ReinforcementLearning v0.7.0

Diff since v0.6.0

Closed issues:

• How to define a new environment? (#64)
• Question about AbstractEnv API (#68)
• Compatibility issue in ReinforcementLearning & Flux (#74)
• ERROR: KeyError: key "ArnoldiMethod" not found (#79)
• I get NNlib error when trying to load a model (#82)
• "convert" warning (#83)
• Seg fault on macbook pro (#84)