Initialise resources when service is created.

Without this, calls to validate_template will fail until the first
parser.Stack is created.

resources.initialise() is called in EngineService __init__
to avoid this happening in another service method in the future
Fixes: bug #1181045

Change-Id: I68a74ec7993aff4b74d449a3ae33315b93e9cb0d
Merge "Initialise resources when service is created."