make appbundle target for OSX development
make appbundle target for OSX development

Adds an 'appbundle' target that creates a top-level Bitcoin-Qt.app/
Modifies the 'deploy' target so that it leaves behind Bitcoin-Qt.app;
make clean will remove it.

syscoin/syscoin,domob1812/crowncoin,syscoin/syscoin,Crowndev/crowncoin,domob1812/crowncoin,syscoin/syscoin,Infernoman/crowncoin,Crowndev/crowncoin,Infernoman/crowncoin,Crowndev/crowncoin,syscoin/syscoin,Infernoman/crowncoin,syscoin/syscoin,Infernoman/crowncoin,syscoin/syscoin,domob1812/crowncoin,Crowndev/crowncoin,Infernoman/crowncoin,domob1812/crowncoin,domob1812/crowncoin,domob1812/crowncoin,Crowndev/crowncoin,Infernoman/crowncoin,syscoin/syscoin,syscoin/syscoin,Crowndev/crowncoin