Dictionary Dependency Improvements, master branch (2018.12.12.)

Here I started to address some issues discovered in ATLINFR-2843 (and also some previous MRs).

First off I tried to add code that would teach Ninja how to re-generate dictionaries in all cases when they need to be re-generated. Unfortunately though that's not working correctly yet. See:

https://cmake.org/pipermail/cmake/2018-December/068738.html

So switching the CI back to Ninja is still not recommended, even after this update.

It does address one other issue though. This one:

https://gitlab.kitware.com/cmake/cmake/issues/18695

At least it seems to address it in most cases. (I've seen a bit of an unexplained behaviour with the code, where sometimes it didn't correctly detect upstream changes coming from headers only included in the auto-generated dictionary header. And other times it did detect those changes. )

All in all, both changes should make our code more robust.

AE Build SUCCESS
Build logfiles are available at Jenkins [AE-MERGE-REQUEST #646]

merged

mentioned in commit b3c2a937

mentioned in commit 36b51b90

mentioned in merge request !405 (merged)

mentioned in commit 324f2b8f

mentioned in merge request !406 (merged)