Fixing the default ctor of wxStandardPaths in wxWidgets influence all OS platforms for Phoenix

wxPython Users
1

Robin, please review this commit and note that the fix to wxStandardPaths was made for all OS platforms (Windows, Mac OS X, Linux/Unix): https://github.com/wxWidgets/wxWidgets/commit/38aae140acbfd562df1388ae76108efcc52f871c