Changes

Seperated unit tests (newt/awt/headless) and cleaned up some imports and comments

Seperated unit tests (newt/awt/headless)
- no more *CORE* tests

- junit.run.newt.headless: all NEWT headless (no-AWT) tests,
  without any AWT classes and with -Djava.awt.headless=true.
  Disabled for 'isOSX'.

- junit.run.newt: all NEWT non AWT tests (same as above),
  but with full AWT. This test is not enabled via junit.run.
  Disabled for 'isOSX'.

- junit.run.awt: all AWT tests without NEWT
  - using newt.event.jar to add AWT agnostic NEWT event adapter

- junit.run.newt.awt: all NEWT + AWT tests

- junit.run: junit.run.newt.headless,junit.run.awt,junit.run.newt.awt

- swizzling around a few tests to achieve the above:

  TEST rules:
   - A runnable unit test must start with 'Test'

   - Only pure NEWT tests must have 'NEWT' in their name

   - AWT tests must have 'AWT' in their name.

   - AWT + NEWT tests must have '.newt.' in their package name, hence

   - Pure AWT tests (without NEWT) must not have '.newt.' in their package name