add initial release notes

Change-Id: I13fa31c4afa6d8d40f75c896f7fb0cfff175f9bc

releasenotes/notes/fix-ceilometerclient-init-8bc7a6742937c3e2.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - >
+    [`bug 1518447 <https://bugs.launchpad.net/aodh/+bug/1518447>`_]
+    Fix to ensure ceilometerclient is properly initialised on startup.

releasenotes/notes/fix-combination-alarms-8097adf08b837a50.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - >
+    [`bug 1511252 <https://bugs.launchpad.net/aodh/+bug/1511252>`_]
+    Fix an issue with combination alarms where it fails to evaluate
+    all issues in the chain of alarms.

releasenotes/notes/fix-gnocchi-aggregation-eval-7c2c1c67bdf2d11c.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - >
+    [`bug 1513738 <https://bugs.launchpad.net/aodh/+bug/1513738>`_]
+    Fix an issue where alarms using Gnocchi aggregations are not being
+    evaluated.

releasenotes/notes/queue-communication-1b884feab4078dde.yaml

@@ -0,0 +1,16 @@
+---
+features:
+  - >
+    Support for queue based communication between alarm evaluator service and
+    alarm notifier services was added. Original implementation involved using
+    RPC but there is significant overhead involved with using RPC. Work queues
+    provided required functionality with better performance.
+upgrade:
+  - >
+    Queue based communication is the new default IPC protocol. RPC can still
+    be used by choosing rpc as ipc_protocol option. Only one protocol can be
+    run at any given time.
+deprecations:
+  - >
+    Because queues provide the equivalent functionality. RPC support is
+    deprecated and will be removed after Mitaka.

releasenotes/notes/remove-eventlet-18ada1cff213af5e.yaml

@@ -0,0 +1,4 @@
+---
+features:
+  - >
+    Remove eventlet from Aodh in favour of threaded approach