xtrn: Don't rely on %3u to provide initial indentation.

If a sysop would like to decorate the number used to select a door program, then %3u is going to put spaces in the wrong place. For example. I like mine to look like this:

However, it seems impossible to achieve without altering the code, which makes it difficult to keep in step with any changes.

Maybe there should be an "initial_margin" or some padding option that will make sure the first part (number) always lines up to the left.

Otherwise I end up with something junky like this.

I can't imagine I'm the only sysop that's going to have this issue so prefer it fixed at the base level. Either that or I'm missing something.