Add a gidocgen/__main__.py
This allows gidocgen to be run with:
python3 -m gidocgen
avoiding ambiguity about whether the correct Python binary is being
used to execute the module. (A problem with scripts like gi-docgen.py
,
especially in venvs, is that their shebang lines will run the wrong
interpreter, and their sys.path
manipulations can end up failing
to pull in the correct module.)
The __main__.py
is basically a neutered version of gi-docgen.py
with the sys.path
manipulations removed (unnecessary as it's guaranteed to be executing inside the package, and uses relative imports), and only thy Python version check remaining.