rebase -i: quick/inline reword

Currently, `rebase -i` allows modifying the commit titles in the list, and the modified title is shown in the lists of previous and next commands, but the changes are not saved. Currently, modifying just the titles of many commits requires `reword`ing each one and separately and consecutively editing each message, which is annoying when making small, repetitive edits, especially since it requires double-checking each one separately. It would be much easier if there were a mode where any changes to the commit titles in the list modified the commits' titles. Maybe `git rebase -i --reword`?

Any thoughts, suggestions, questions, etc.?

FYI, I am using git version 2.20.1 on `Linux ghostwheel 4.19.0-8-amd64 #1 SMP Debian 4.19.98-1 (2020-01-26) x86_64 GNU/Linux`.

Solomon Ucko

P.S. This is my first time posting here, so let me know if I accidentally violated any rules, e.g. etiquette or formatting.