updated wall papers on tips and videos page
Updated TestFlight SDK to 1.2.4
Added images for blog and tips
Added TestFlight instrumentation
Other files with the instrumented TestFlight points
fixed bug where app would not refresh content from the web.
major refactor of the data models: create a singleton to manage the models to help fix the bug above

created bios.plist with bios and also placed a copy on the web so the bios can be dynamically updated
part of previous commit