Fix T40839: Object Font Text Rendering Bug

The issue was caused by the wrong objects order for
convertblender.c. Dependency graph totally missed
handling of this situation.

Fixed now, but it's not that pretty, don't try this
at home obviously. But consider this to be good enough
for the current dependency graph.

Details are in the build_dag_object().
Make clone tool UI slightly less horrible.

Move clone tool options as well as layer selection to the brush panel.
That should make its use more apparent and, most importantly, easy.
Fix T41086: VSE separate images increases file size abnormally.

We were copying everything from the old sequence into each new ones... including the stripdata,
which for image sequences is an array with one item per image!

So bug was an exponential one, separating strips of a few tens of images was insensible, while
separating a strip of 1000 images would add above 250MB to file size (and RAM usage too)!
Fix missing include
Cleanup: pep8 & redundant vars
initial intersect code
initial isect
intersection script
test vert intersection
check for intersections where no new verts are added first
minor fixes
WIP