[infrastructure] [macos] use QGIS-Mac-Packager dependencies to setup MacOS CI build with GitHub workflows. Use CMake's define QGIS_MAC_DEPS_DIR to define folder to dependencies
Search for libraries first, before includes, so any frameworks found can
have their Headers subdirectory added to search paths for includes.
- Reintroduce qwt and qscintilla2 base library names for searching.
* pyqtwrappers update (add QtNetwork, QtXml, QtSql, QtTest, uic)
* 2to3 updates
* move QPyNullVariant/NULL to PyQt.QtCore
* add global unicode/basestring/long for Python3
* expand QtGui, QtCore module and star exports
* Qscintilla2
* replace Set import with set builtin
- Needs testing on Windows platform
- Add QScintilla2 library version info to About dialog
- Add Mac bundling support for Qwt 6 framework and QScintilla2
- Fallback to sys or custom site-pkgs when looking for PyQt4 modules to Mac bundle