Correct misspellings in code comments of "vertex" and "vertices".
The singular of vertices is vertex, NOT vertice. Interestingly, for a plural, both "vertices" and "vertexes" are considered correct, though Blender is pretty consistent with using the former and we should stick with that.
There are several files where this misspelling was present in the code. This diff fixes them.
Sources:
https://www.merriam-webster.com/dictionary/vertex
https://www.merriam-webster.com/dictionary/vertice
(Note addons are guilty of this too, and I have an upcoming patch to address those.)