FWIW, basic machine learning approaches to "sentence boundary detection" (as the task is called) get 199 out of 200 of these right (without using the "two space" clue), and have for a while. (e.g., http://sonny.cslu.ohsu.edu/~gormanky/blog/simpler-sentence-b...)
For the purpose of version control, it doesn't even have to be exact. It doesn't matter if the detector inserts an incorrect line break after a certain combination of characters, as long as it does so consistently so that it produces a readable diff.