Fixes #4716: correct the ordering of promises writing
Merge pull request #38 from ncharles/bug_4716/dev/error_in_promise_generation

Fixes #4716: correct the ordering of promises writing
Merge branch 'branches/rudder/2.9' into branches/rudder/2.10

Conflicts:
	src/main/scala/com/normation/cfclerk/services/impl/Cf3PromisesFileWriterServiceImpl.scala