* adds valgrind to new object manager.

* Add some comments.

* Update run_object_manager_valgrind.sh

typo

* Update run_object_manager_tests.sh

* update tests to reflect changes in #1891.

* reduce # tests.

* cache all object info from object added store notification.

* Adds parallel transfer for big objects.

* documentation and clean up.

* compare objects...

* merge buffer_state with chunk vec. Make separate buffer state for get and create.

* use references for Get. Allow partial failure of Create.

* single plasma client.

* changes based on review.

* update documentation and add parameters for object manager in main.cc.

* review feedback.

* use vector consturctor.

* linting

* remove profile visualizations.

* test fixes.

* linting.

* kill specific pids and use less memory.

* linting.

* simplify tests.

* Asynchronous IO for ObjectManager messages and object transfer.

* Revert "Asynchronous IO for ObjectManager messages and object transfer."

This reverts commit 4af43b1.

* update test configuration to reflect changes in #1891

* review feedback.

* linting.

* master: (56 commits)
  [xray] Turn on flushing to the GCS for the lineage cache (ray-project#1907)
  Single Big Object Parallel Transfer. (ray-project#1827)
  Remove num_threads as a parameter. (ray-project#1891)
  Adds Valgrind tests for multi-threaded object manager. (ray-project#1890)
  Pin cython version in docker base dependencies file. (ray-project#1898)
  Update arrow to efficiently serialize more types of numpy arrays. (ray-project#1889)
  updates (ray-project#1896)
  [DataFrame] Inherit documentation from Pandas (ray-project#1727)
  Update arrow and parquet-cpp. (ray-project#1875)
  raylet command line resource configuration plumbing (ray-project#1882)
  use raylet for remote ray nodes (ray-project#1880)
  [rllib] Propagate dim option to deepmind wrappers (ray-project#1876)
  [RLLib] DDPG (ray-project#1685)
  Lint Python files with Yapf (ray-project#1872)
  [DataFrame] Fixed repr, info, and memory_usage (ray-project#1874)
  Fix getattr compat (ray-project#1871)
  check if arrow build dir exists (ray-project#1863)
  [DataFrame] Encapsulate index and lengths into separate class (ray-project#1849)
  [DataFrame] Implemented __getattr__ (ray-project#1753)
  Add better analytics to docs (ray-project#1854)
  ...

# Conflicts:
#	python/ray/rllib/__init__.py
#	python/setup.py