[PyQt] Version info for PyQtWebEngine

[Detlev Offenbach]

Hi Phil,

with PyQt 5.13.0 the PyQtWebEngine was packaged separately from PyQt5. This is 
comparable to what was done with PyQtChart. The later contains version info 
(string and int) but PyQtWebEngine doesn't. Wouldn't it be beneficial, to have 
these as well (i.e. PYQT_WEBENGINE_VERSION and PYQT_WEBENGINE_VERSION_STR)?

Regards,
Detlev
-- 
Detlev Offenbach
detlev at die-offenbachs.de