Addons missing in Makefile

[sbl]

Several addons are missing in at least in ​https://github.com/OSGeo/grass-addons/blob/master/grass7/raster/Makefile

If there is no specific reason for excluding them, missing addons should be added so manuals are generated.

Maybe even better do point to all subdirectories in raster, vector, ... by default? E.g. like here: ​https://stackoverflow.com/questions/17834582/run-make-in-each-subdirectory

Then addon devs do not have to remember this...