[+] several interfaces
Remove Anton's realizations of tasks
Add debug option
Add algo "segment contains point" with tests (from Anton) and vis
Little change comment add remove unnecessary "cg::"
Add algo "triangle contains point" with tests and vis
Add algo "segment intersect segment" with tests and vis
Rename class
Add algo "segment intersect triangle" with tests and vis
Remove unnecessary comment
Disable test (very slow, but OK)
Merge branch 'interfaces' into work

Conflicts:
	include/cg/primitives/contour.h
Fix bug in draw util
Improve rectangle primitive. Add [] and set_corner function (usefull for print in vis)
Add algo "rectangle contains point" with tests and vis
Add algo "segment intersect rectangle" with tests and vis
Add file to previous commit
Fix warning
Add algo "contour is counterclockwise" with test
Reorganization of visualisations