It is unclear how to save a change to your commit message within the MR widget

Currently when you want to modify the commit message with the MR widget, you see the following:

Screen_Shot_2017-07-27_at_2.13.13_PM

Clicking the merge button is how you save the commit message. This is unclear, since it is unrelated to changing your commit message and the button is located above the form.

We should add a button to save the changes separately from merging the MR. Example:

Screen_Shot_2017-07-27_at_1.46.21_PM