Resolve "Prevent code duplication in python codegen"

Closes #103 (closed)

Managed to reduce about 200 lines by not have duplicated templates. Since the total git diff is no so easily understandable I did two commits, the first only removes the old functions and the second adds the new. So you can see commit by commit and the total diff, which ever way you like.

changed milestone to %3.0.0

added silecs-codegen label

requested review from @al.schwinn

Thank you, @m.marn, much more granular than I was thinking, though looks good to me ! .. lets merge it.

Just noticed that we forgot to add an enum into AllTypesFESA.silecsdesign ... will open a separate issue for that.

Done (#105 (closed)), added it to the 3.0.0 milestone(I hope you have some time left for silecs?)

Yes, I can do it in this milestone.

merged