www/py-djblets: update to 0.9.1

• update to 0.9.1
• switch MASTER_SITES to PyPi (cdn)
• actualize dependencies
• add NO_ARCH, because there isn't platform-dependent code
• add more files to shebang changing list
• pass maintainership to python@

Since version 0.9.1 djblets supports Django 1.8, while it still depends upon
www/py-django-pipeline13 (that requires Django 1.6), so I keep this dependency
unchanged to prevent django versions clash.

In not yet released version 0.10 djblets now depends on django-pipeline 1.6.6,
so after release we can completely switch this port to using Django 1.8