Added a little dialog for iPhone Users.

This prompt appears if the user is on an iphone and tells them they can
add pose to their home screen. All changes are to accomodate that except
in responsive:

- Made it so the filters change at 730px screen width so ugliness is
avoided.
- Made the Member's Area take up all of the screen width. I am thinking
of restricting this again and trimming body whilst this is active?
- Made Edit profile fields fit on screen
- Made Challenge/Response Names fit better (Still going to be an issue
but now they are clickable
- added margin to edit user fieldset