Refactored coregl-utils-examples; minor changes to CoreSetupJogl

coregl-utils-examples:
-Renamed dir coregl-utils-lwjgl-examples -> coregl-utils-examples
-Removed CoreExample, all classes now again implement only RenderLoopCallback
-Removed all runJogl/runLwjgl methods
-CoreExampleMain now handles CoreGL and CoreSetup initialization separately for JOGL and LWJGL.
-Updated references in all example classes to work with changes

coregl-utils-jogl:
-CoreSetupJogl now uses exclusive context thread to prevent unnecessary overhead from thread context switching