Merge pull request #1 from bpeisenbraun/master

Add an ignore file and raise the splash window.
Merge pull request #2 from bpeisenbraun/master

Add datadir setting to find images from inside app bundles.
version number -> 1.23
App bundle updates for 1.23.

 - add Info.plist with file type registration.
 - add simple Makefile to streamline bundle building.