Bug 1048: Add unit tests demonstrating multiple NewtCanvasAWT instances are working

Enhance following performance test cases, adding NewtCanvasAWT,
beside GLCanvas and GLJPanel, 25 instances:
  com.jogamp.opengl.test.junit.jogl.perf.TestPerf001GLJPanelInit01AWT
  com.jogamp.opengl.test.junit.jogl.perf.TestPerf001GLJPanelInit02AWT

Adding simple com.jogamp.opengl.test.junit.newt.TestMultipleNewtCanvasAWT
w/ two instances.

Manually tested on GNU/Linux and OSX (java7 and java8).