fat commit

[+] some operations. I'll push some interfaces, pull implementation for
them
[+] triangle_contains_point example
[+] bug fixes
[+] several interfaces
Merge branch 'contour_fix'
Intersection of segment and rectangle optimized
Merge remote-tracking branch 'origin-main/interfaces'

Conflicts:
	include/cg/operations/orientation.h
	include/cg/primitives/contour.h
	include/cg/primitives/rectangle.h
	include/cg/primitives/triangle.h
	tests/CMakeLists.txt
Merge remote-tracking branch 'origin-main/master'