Add Docker Support for ASV (#2184)

* added new instructions and script

* initialize ray only once

* use ray-project/asv master

test/jenkins_tests/run_asv.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+# Cause the script to exit if a single command fails.
+set -e
+
+# Show explicitly which commands are currently running.
+set -x
+
+git clone https://github.com/ray-project/asv.git /tmp/asv/ || true
+cd /tmp/asv/
+pip install -e .
+
+cd /ray/python/
+asv machine --yes
+asv run --show-stderr --python=same --force-record-commit=$(cat ../git-rev)