* bugfix: env exists check error
* support to avoid re-build pyarrow in project
* bugfix: adapt gtest for centos lib64
* bugfix: check gtest lib exists in the directory
* bugfix: find gtest with checking all libs exists
* prefix RAY_ to thirdparty env variables to avoid conflicts with other module
* arrow use glog from ray
* change the glog and gtest install dir
* enable using thirdparty env variable to find installed dependency, to speed up the build process
* fix target dependency in cmake. :-) too chaos in each CMakeLists
* check env variable defined directory exists