Add PyQt5 support

This PyQt5 support is a port of the PyQt4 hooks and helper functions.
It may not yet be complete.
Remove QtV8 from PyQt5 hooks
Remove QtV8 from PyQt5 hooks
Add QtQml
Update comments, fix formatting
Merge branch 'develop' of github.com:glennra/pyinstaller into develop
Fix formatting
Add test for PyQt5 and Qml
Fix removal of QT_PLUGIN_PATH from environment
Fix line wrapping
Merge branch 'develop' of https://github.com/pyinstaller/pyinstaller into develop
Fix exit behaviour of PyQt5 Qml test
Merge pull request #70 from glennra/develop

Add PyQt5 support