TTL is no longer necessary, but keeped for protection in DEBUG
Prograde direction: add some idea and reorder items
new predicats + rewrite predicats
New function used currently by Face for collision
Use of geometry built-in function
Open geometry files
divide flipOn() into 2 methods for reusability and readability
Delete useless comments lines (old DEBUG)
Write delVertex() method
Just some help when very bad things happened
Some unoptimized and useful privates methods for vertex deleting
Clean code + corrections on Delaunay condition restoration
Actualize README: example, prograde direction
New version: Vertex can be deleting