Enable measure widths to be aligned down a page and allow "r" to preserve layout format.

I use museScore to create exercises for drummers where going down the page measures must be the same width as those above and below. It takes a lot of juggling to make these close to alignment, especially if there are any horizontal frames in a line. It would be useful to be able to copy the layout format of a line from one line to the next. Using "r" doesn't preserve layout format.