Switch build system to use CMake completely. (#200)

* switch to CMake completely

...

* cleanup

* Run C tests, update installation instructions.

python/ray/workers/default_worker.py

@@ -0,0 +1,61 @@
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+import argparse
+import numpy as np
+import redis
+import traceback
+
+import ray
+
+parser = argparse.ArgumentParser(description="Parse addresses for the worker to connect to.")
+parser.add_argument("--node-ip-address", required=True, type=str, help="the ip address of the worker's node")
+parser.add_argument("--redis-address", required=True, type=str, help="the address to use for Redis")
+parser.add_argument("--object-store-name", required=True, type=str, help="the object store's name")
+parser.add_argument("--object-store-manager-name", required=True, type=str, help="the object store manager's name")
+parser.add_argument("--local-scheduler-name", required=True, type=str, help="the local scheduler's name")
+
+def random_string():
+  return np.random.bytes(20)
+
+if __name__ == "__main__":
+  args = parser.parse_args()
+  info = {"node_ip_address": args.node_ip_address,
+          "redis_address": args.redis_address,
+          "store_socket_name": args.object_store_name,
+          "manager_socket_name": args.object_store_manager_name,
+          "local_scheduler_socket_name": args.local_scheduler_name}
+  ray.worker.connect(info, ray.WORKER_MODE)
+
+  error_explanation = """
+This error is unexpected and should not have happened. Somehow a worker crashed
+in an unanticipated way causing the main_loop to throw an exception, which is
+being caught in "lib/python/ray/workers/default_worker.py".
+"""
+
+  while True:
+    try:
+      # This call to main_loop should never return if things are working. Most
+      # exceptions that are thrown (e.g., inside the execution of a task) should
+      # be caught and handled inside of the call to main_loop. If an exception
+      # is thrown here, then that means that there is some error that we didn't
+      # anticipate.
+      ray.worker.main_loop()
+    except Exception as e:
+      traceback_str = traceback.format_exc() + error_explanation
+      error_key = "WorkerError:{}".format(random_string())
+      redis_host, redis_port = args.redis_address.split(":")
+      # For this command to work, some other client (on the same machine as
+      # Redis) must have run "CONFIG SET protected-mode no".
+      redis_client = redis.StrictRedis(host=redis_host, port=int(redis_port))
+      redis_client.hmset(error_key, {"message": traceback_str,
+                                     "note": "This error is unexpected and should not have happened."})
+      redis_client.rpush("ErrorKeys", error_key)
+      # TODO(rkn): Note that if the worker was in the middle of executing a
+      # task, the any worker or driver that is blocking in a get call and
+      # waiting for the output of that task will hang. We need to address this.
+
+    # After putting the error message in Redis, this worker will attempt to
+    # reenter the main loop. TODO(rkn): We should probably reset it's state and
+    # call connect again.