* fix minor probmels in the docs

* typo

* remove pip source

* fix monitor

* add performance of A2C

* Update README.md

* modify logger for GPU detection

* upgrade unit test to reduce test time

* minor change

* fix the bug in unit tests

* fix the bug in build.sh

* Update build.sh

* Update test.sh

* fix a potential bug that will hung the test

* then

* solve the problem in documentation

* fix a number of bug

* update comments

* paddle license

* revert the change on client_not_init_test.py

* fix timeout bug & unnitest

* add unit test for potential bugs

* yapf

* unit test

* logger

* logger#2

* fix job's bug that will cause dead-lock

* fix bug

* add missing files

* solve hanging

* fix comments; exit job completely

* hanging problem

* hanging problem#2

* hanging_program#3

* CMAKE

* remove unused variables

* fix the compatibility issue

* fix the comment issue

* support paddle 1.5.1 and replace PE with compiler

* yapf&copyright

* yapf

* fix the teamcity problem

* fix the teamcity problem

* fix comment

* only support paddle 1.5.1

* Cmake

* fix comment

* add unittest for compling the docs

* record the time of change

* remove unused requirements

* reduce font size of the changelog

* support serialize/deserialize instance of custom class

* update version requirement of dependences

* remove requirements of unittest which are included in parl

* use fashion style of pyarrow serialization context; add thread safe unittest of serialize/deserialize

* add thread-safe test of remote module; add more exception tips of serialize/deserialize

* refine comment

* add test for import parl

* fix error of check_style

* change pip source

* refine naming

* Update README.md

* Update Dockerfile

* Update build.sh

* add api set_params/get_params in Model; add Interface of Network and LayerFunc to solve circular imports; refine parameter_names api of Model

* remove licence in third party code; remove interface of Network and LayerFunc; move get_parameter_pairs and get_parameter_names api to Network

* refine comment

* refine commment

* run unittest in python2 and python3

* refine structure of repo

* refine structure of repo

* add --fix-misssing

* fix teamcity

* add --fix-misssing

* update paddle version in python2