Release Mistral 2.0.0 beta 1

Per the new process [1], we now need to tag milestones. Here is the
2.0.0.0b1 release for the mistral project.

[1]
http://lists.openstack.org/pipermail/openstack-dev/2015-November/080692.html

Change-Id: I86853cebe222d5537ec46a8999961e832110314a

deliverables/mitaka/mistral.yaml

@@ -0,0 +1,7 @@
+---
+launchpad: mistral
+releases:
+  - version: 2.0.0.0b1
+    projects:
+      - repo: openstack/mistral
+        hash: e398f9c5ff3e860fccae1a8257451a60b02506d1