OS compatibility update

Updated for better compatibility with more recent iOS versions

Added Core MIDI support, better iOS 7 support, plus a few bug fixes.

Updated for iOS6 & the larger iPhone 5 display.
Added a new more realistic autoharp sound option.  (The old sound bank is still there for compatibility with the previous release.)
New Icon.

Improved responsiveness.
New string animations.
iOS5 compatibility fixes.

Bug fixes for 2 finger strumming and plucking.
Bug fixes for configurable chord defaults restore and save.

Added iPad full-screen compatibility.
Improved string sounds.

Polyphonic synthesizer updated for improved responsiveness and significantly less latency.