Basic structure of extension methods
Set to keep track of vertices in the cycle
small typo in a comment
Methods to determine orbits of edges
Code to find addable edges and determine the orbits of these edges
Some extra comment
Basic structure for making the extension for each orbit of addable edges
Keep track of vertices in cycle
Added methods to check canonicity of the last operation
Make sure we only consider real edges and not subdivided edges while building the list of possible extensions