Invalid glEnable in GLRenderable.beginDraw

gl.glEnable(GL2.GL_SMOOTH) is an invalid attribute. I get a JOGL error.

Should be gl.glShadeModel(GL2.GL_SMOOTH);

Also, this bug caused GL stack problems because it threw an exception, which popped back up to the finally clause in myRender(). finally called endDraw() which does an unneeded gl.glPopMatrix(), but gl.glPushMatrix() never happened in the beginDraw, due to the exception.

Anyway, exception handling needs to be re-worked here.