Pull Plasma from Apache Arrow and remove Plasma store from Ray. (#692)

* Rebase Ray on top of Plasma in Apache Arrow

* add thirdparty building scripts

* use rebased arrow

* fix

* fix build

* fix python visibility

* comment out C tests for now

* fix multithreading

* fix

* reduce logging

* fix plasma manager multithreading

* make sure old and new object IDs can coexist peacefully

* more rebasing

* update

* fixes

* fix

* install pyarrow

* install cython

* fix

* install newer cmake

* fix

* rebase on top of latest arrow

* getting runtest.py run locally (needed to comment out a test for that to work)

* work on plasma tests

* more fixes

* fix local scheduler tests

* fix global scheduler test

* more fixes

* fix python 3 bytes vs string

* fix manager tests valgrind

* fix documentation building

* fix linting

* fix c++ linting

* fix linting

* add tests back in

* Install without sudo.

* Set PKG_CONFIG_PATH in build.sh so that Ray can find plasma.

* Install pkg-config

* Link -lpthread, note that find_package(Threads) doesn't seem to work reliably.

* Comment in testGPUIDs in runtest.py.

* Set PKG_CONFIG_PATH when building pyarrow.

* Pull apache/arrow and not pcmoritz/arrow.

* Fix installation in docker image.

* adapt to changes of the plasma api

* Fix installation of pyarrow module.

* Fix linting.

* Use correct python executable to build pyarrow.

python/ray/experimental/state.py

@@ -465,7 +465,7 @@ class GlobalState(object):
                         **params)
 
             for (event, score) in event_list:
-                event_dict = json.loads(event)
+                event_dict = json.loads(event.decode())
                 task_id = ""
                 for event in event_dict:
                     if "task_id" in event[3]: