feature: Add MAAC Trainer (#48)

* Update maac.py

* Update maac.py

* monkey patch

* Update maac.py

* set td or mc update critic configurable

* add early termination

* add eval

* remove monte carlo update

* Update maac.py

* remove variance cal

* Update maac.py

* Update magrpo.py

* remove redundant logic and change step

Author: LovelyBuggies