Adding tests for PText

Adding tests for PText and making it return empty string by default rather than null. More inline with JTextField

Fixed a memory leak with PCanvas instances registering themselves with KeyboardFocus and never unregistering themselves. ...

Added a Hierarchy listener so that the inputsources are installeded and uninstalled when a canvas gets added or removed to a parent.

Fixed Issue 100; Plastered PInputEventFilter with Unit Tests and then made it consider the masks conditionally. ...

andMask if it's non-zero
notMask if it's non-zero
orMask if it's not ALL_MODIFIERS (I can't think of a case where you might want to say, "Only allow events as long as they have a modifier, I don't care which one")

Fixed Issue 91; deprecated repaintFromlayer(PBounds, PNode) in favor of the more specific repaintFromlayer(PBounds, PLayer) making it impossible to accidentally pass a camera say to this method.

Fixed Issue 96; Made PAffineTransform throw PAffineTransformException (a subclass of RuntimeException) whenever a non-invertible transform is encountered. ...

In the process, I removed 2 printStackTrace calls from the code base.

Fixed Issue 92; make it check for empty stack before popping the cursor

Fixed Issue 94; made removeLayer(PLayer) "fail" silently. Also added some additional tests and refactoring. Sorry for such a large commit, I'd try to split it up, but it's hard to tell what's safe to leave out and what's not. I know that the whole together unit tests fine. I have to remember to checkin more frequently.

Simplifying getInverseTransform and making it not call printStackTrace() since it was handling that case anyway. Issue #96 may make this a non-issue anyway.

Added some trivial tests for PPanEventHandler and added come accesors to it for maxAutoPanSpeed and minAutoPanSpeed. ...

Also, cleaned up test for PAffineTransform.

Folding nested if statements into themselves. Makes PMD stop complaining so loudly.

Refactored PDebug code so that PMD didn't complain about two ifs that could be joined. In the process making it slightly clearer.

Replaced complex xor logic with Java's xor operator.

Part of a solution to Issue #53; made toImage not use GraphicsEnvironment in the case of running in Headless mode.

Added accessors for render quality on PCanvas (Issue 93) , and also wrote more tests to confirm that Issue 87 is fixed.

Added some move tests to PCanvas

made toImage(int, int, Paint) return an image of the size requested. Since it seems that the resizing is already done in PNode.paint it was just a matter of deleting the resize code. ...

Also, I've added 3 tests to PNodeTest that try and confirm the behavior.

Added some more tests for PCamera and broke MockPropertyChangeListener out into its own top level class. Also, cleared up some wording in comments.

Marked position as @deprecated, and make animateToRelativePosition public (from package private).

Modified PNode so that it retained public interface clirr. I'll run that from now on. Thanks, and sorry heuermh

Pushed up UnitTest Instruction Coverate of PNode up to 90.1% and reorganized PNode slightly so that it was easier to test position.

Issue 59 ; updating license date range to include 2009

set opacity to be true by default, to make sure changes are compatible with new support for transparent pcanvas (see PCanvas.paintComponent)

Issue 23 ; check for existence of a node before removal to prevent NullPointerExceptions

Issue 19 ; added reference to PCamera as PInputEvent input source in cases where path is null

Issue 17 ; refactoring PCanvas KeyListener to KeyEventPostProcessor

Issue 15 ; properly consume mouse events in PSwing components

added support for non-opaque canvas, see http://groups.google.com/group/piccolo2d-dev/browse_thread/thread/134e2792d3a54cf

Issue 59 ; copyright start year should be 1998 to match oldest files

Issue 59 ; updating license header and adding one where missing