Default payment processor should appear first in Payment Method radio button for online contribution page and online event registration

1. Modify online registration and event form payment_processor radio button so that DEFAULT payment processor appears first if multiple processors are offered.

2. Default processor radio button was NOT pre-selected on event registration pages, so we need to fix that in Register::setDefaults()

---- Original Post —
Tested on 4.3beta5.

1. Create several payment processors.
2. There is no way to select the order of the processors as they display on a contribution page.
3. This might be ok if the default was first, or if they were alphabetical, but the processors are listed only in the order of their creation.

solution: place default first, or better yet allow re-ordering of processors