* Changes to the build system for support java worker
--------------------------
This commit includes changes to the build system, which is part of the java worker support of Ray.
It consists of the following changes:
- the changes of CMakeLists.txt files
- the changes of the python setup.py and init files for the adaptation of the changed build system
- move the location of local_scheduler_extension.cc for the adaptation of the changed build system which maybe better support multi-language worker
* minor whitespace
* Linting