(cherry picked from commit 53fca645)

(cherry picked from commit 1e8f0db6)

Compiler error fix

Closes #18 

See merge request !42

Cdt fix



See merge request !40

(cherry picked from commit 55d08748)

Python decimater



See merge request !38

Om6.0 with python

Merge with some disabled python tests in ci


See merge request !36

(cherry picked from commit 180a55e8)

Iterator increment



See merge request !35

fix crash in OMWriter when writing an empty mesh with colors

Writer accessed VertexHandle(0) for meshes with colors even when they had no vertices.

See merge request !34

Python ci



See merge request !33

(cherry picked from commit d119277f)

Om6 code reduction

Reduce number of includes

See merge request !32

(cherry picked from commit d4a361aa)