Add Docker Support for ASV (#2184)

* added new instructions and script

* initialize ray only once

* use ray-project/asv master

python/benchmarks/benchmarks.py

@@ -7,7 +7,9 @@ import ray.test.test_functions as test_functions
 
 
 def setup():
-    ray.init(num_workers=4, num_cpus=4)
+    if not hasattr(setup, "is_initialized"):
+        ray.init(num_workers=4, num_cpus=4)
+        setup.is_initialized = True
 
 
 class TimeSuite(object):