Previously oslo.messaging's MessageHandlingServer
was used as as a murano-engine service in service launcher.
As a result it's wait() method was called. But after recent
changes it's wait method is supposed to be call only
after stop() to wait for graceful message processing to end.
As a result a warning was printed that stop() didn't finish
after 30 sec from wait() invocation (because it was never called).
This commit adds EngineService service implementation
that has its own wait() and encapsulates MessageHandlingServer
instance.
Change-Id: Ie553e0b27cc1c261b963907b4f12f89795b99a12
Closes-Bug: #1521087
05edab3661