Support more word-processor-like fill behavior

[NateEag]

I discovered aggressive-fill-mode recently and was delighted to find it existed - I've wished it was around for years.

I have some prototypical work in my .emacs.d that lets you fill even more aggressively:

• fill after all self-inserts
• fill after deletes/yanks, by advising whatever functions the user configures.

With these two changes, writing plain text files and source code comments feels a lot like working in a word processor - text almost always flows naturally.

Is this line of work something you'd be interested in merging?

If so, what changes would you want to see to it?

(also, my apologies for any bogus notifications you received - my keyboard betrayed me, and I initially opened this as a content-free issue named 'w'.)