Fix for Retina Display on Mac #248

Hi folks,

this update fixes the problem on retina macs #248.
I needed to update QScintilla component to 2.8.4,
and added an new entry into Info.plist.

When you compile by yourself make sure you remove your old version from applications folder,
because Mac OS X caches the Info.plist.

I tested with QT 5.3.2 and cmake 3.0.2 on Mac OS X 10.10.1 ...

Best regards
Michael