Normalize build type to a value with a well defined and documented case

[bast]

This is to simplify if checks in the code without worrying too much about the case.

[miroi]

Hi, so 0 will be OK, but how many ending scenarios will autocmake builds have ?

[bast]

Sorry I am not sure I understand the question. This issue is about normalizing release, RELEASE, Release, etc. to e.g. "Release".

[miroi]

Ah,ok, now I understand.