Trim headline title at both sides before saving

[schoettl]

... when capturing via template and when adding/editing a headline.

Makes sense?

I think it does not make sense to have trailing whitespace in any source code. OK, markdown uses trailing whitespace to declare a <br> but a headline in emacs does not need trailing space, right?

[munen]

Good thinking!

I completely agree that trimming whitespace for a newly created headline is a good idea and that we should do it. There's no semantics to trailing whitespace and having it is likely an input error.

I have added some documentation on where we do trim and where we don't trim trailing whitespace.

Nice addition, thank you @schoettl 🙏

[munen]

I have updated the changelog with the attribution: b7f7a00