+ fix bug in mesh bounding box, fix clang warning
Arch: small fix in sectionplane - fixes #1836
enhancements in exportDRAWEXE.py

simplify float formatting
support for Part::Thickness in exportDRAWEXE.py
support for Draft::Ellipse in exportDRAWEXE.py
support for Annotations
importOpenSCAD: support for projection(cut=true)
+ set DBL_MAX as maximum for units