[FEATURE REQUEST] Add optional toggle to check if a mechanism needs a minimum KPP version

[yantosca]

I was thinking it might be a nice feature to have the ability to add an optional KPP toggle such as #MINIMUM_REQUIRED X.Y.Z so that KPP will throw an error unless you are using version X.Y.Z or higher.

For example, the CMake build system lets you specify a minimum version such as:

cmake_minimum_required (VERSION 3.13)

This might become important for models such as GEOS-Chem where we have many different versions in use. For example, if someone wanted to use a mechanism with the new #AUTOREDUCE capability that @jimmielin and @msl3v are developing, you would need to use KPP 3.0.0 (when it is ready). But if you don't want to use the #AUTOREDUCE feature then you wouldn't need to specify a minimum version.

I can work on adding this to the add-geos-chem-updates branch.

[RolfSander]

Good idea! Two comments:

• I'm not sure how long the command names can be. If #MINIMUM_REQUIRED is too long, maybe #MINVER would suffice?

• Make sure that the new command is analyzed first. Otherwise, the code could crash at an undefined #AUTOREDUCE command even though you have specified a minimum version.

[yantosca]

34 has now been merged into the development branch. We can close this now.

[RolfSander]

Thanks for adding the #MINVERSION feature! I added two minor commits in dev...