Cleanup: rename repo generation script

In attempt to keep this name short, it became acronym-y *and* long. Better
to just pick a clear name which tab-completes.

setup.py

@@ -106,6 +106,7 @@ setup(
     author='Ellwood Zwovic',
     author_email='gandalf3@blendermonkey.com',
     packages=['bpkg'],
+    scripts=['generate_repository'],
     url='https://developer.blender.org/diffusion/BPMA/',
     platforms='',
     zip_safe=False,