+ revert regression with mixing Python debug and release libs
+ fixes #0001363: VRML export can produce corrupt files
+ allow to modify placement via sub-attributes
+ make sure to use valid compression level
+ degree symbol is not 7-bit ASCII, use utf-8
Draft: Fixed polygon center snap
+ fixes #0001845: The Project Utility drops the diffuse colors
+ fixes #0001736: Parts with multiple colors are displayed in a single bad color after hiding
+ check if file handle is valid in FileInfo::isFile