Refs #10439 Update FindPyQt.py and FindPyQt4.cmake from kdelibs.

Trac ticket [#10439](http://trac.mantidproject.org/mantid/ticket/10439).

FindPyQt.py should optionally use PyQt4.QtCore.PYQT_CONFIGURATION in order to determine version and pyqt_sip_flags.

This change is just taken from https://projects.kde.org/projects/kde/kdelibs/repository/revisions/a7e47438d4e3469dc9df70d613826cb360fc8d19

**To Test**: Does cmake still find PyQt4? Good.