Support for different line-wrapping conventions: no two sentences on the same line

The following would be nice to have as an option: only wrap long lines, but do not join two subsequent sentences into one line.

For example:

This is a first sentence.
This is another long sentence, which should not be joined to the
previous one.

Having each sentence on its own line(s) makes it easier to visualize changes in text with git diff.
Otherwise, one small change in a long paragraph may cause many lines to be affected due to rewrapping of subsequent sentences, which makes the git diff output harder to process.

The each-sentence-on-its-own-line convention is something I got used to by working on LaTeX projects in Git, but it is such a nice improvement over rewrapping (manual or automatic), that I started using it in docstrings and markdown files as well.

I can imagine this would not be the preferred convention for everyone, but I would certainly use it, if it were an option.

The issue names no files, tests, or entry points. Start by locating docformatter's line-wrapping implementation and existing option handling, then determine how sentence boundaries and configuration should work; done means an opt-in mode preserves sentence boundaries while wrapping long sentences and has coverage for the example behavior.