[PyQt] [pyqtdeploy] Add support for loading C-extension modules

[Ilya Kulakov]

While pyqtdeploy does not attempt to automatically resolve dependencies,
it should still support loading of extension modules manually put in right directories.
Current implementation looks for extension modules named after their fqmn
next to the executable. In addition the PlugIns and Frameworks directories are checked
on Mac OS X.

https://github.com/GreatFruitAndy/pyqtdeploy/commit/8179fcde656b59f1cd9474c752d4caf70a779f41.patch