Changed `SimpleMesh` api, added validation for edge loops, and face addition via verts.
Changed `SimpleMesh` api, added validation for edge loops, and face addition via verts.

Renamed all the element addition methods to descriptive values that don't shadow the base `Mesh` methods.

Added validation for edge-loops, as well as optional cancellation of validation when adding faces via edge-loops.

Added query to get common edge between verts, and addition of face via vert loops.

5310/aif-mesh