Simplified about page scrolling code

A bit less hacky now. Now scrolls to top or bottom of page without need of a "scrollHeader" or "scrollFooter". Having the storyboard cluttered with these 2 uiviews for the sole purpose of scrolling just seemed silly. Calculating scrolling the proper way now.
Modified about page urls to open in external browser.

Per apple's rejection based partially on a "donations" link being reachable from within the app.
Merge remote-tracking branch 'monte/aboutPage'