fix CPWindow to only sent certain not handled keys as actions

In Cocoa CPWindow will only send moveDown: (down arrow), moveUp: (up arrow), moveLeft: (left arrow), moveRight: (right arrow), pageUp: (page up), pageDown: (page down) and complete: (escape) down the responder chain. This commits makes us fully compatible with Cocoa except that we send scrollPageDown: and scrollPageUp: in stead of pageUp: and pageDown:.

AppKit/CPWindow/CPWindow.j

@@ -2298,8 +2298,46 @@ CPTexturedBackgroundWindowMask
     if ([anEvent _couldBeKeyEquivalent] && [self performKeyEquivalent:anEvent])
         return;
 
-    // Interpret the key events
-    [self interpretKeyEvents:[anEvent]];
+    // Apple's documentation is inconsistent with their behavior here. According to the docs
+    // an event going of the responder chain is passed to the input system as a last resort.
+    // However, the only methods I could get Cocoa to call automatically are 
+    // moveUp: moveDown: moveLeft: moveRight: pageUp: pageDown: and complete:
+    [self _processKeyboardUIKey:anEvent];
+}
+
+/*
+    @ignore
+    Interprets the key event for action messages and sends the action message down the responder chain
+    Cocoa only sends moveDown:, moveUp:, moveLeft:, moveRight:, pageUp:, pageDown: and complete: messages.
+    We deviate from this by sending (the default) scrollPageUp: scrollPageDown: for pageUp and pageDown keys.
+    @param anEvent the event to handle. 
+    @return YES if the key event was handled, NO if no responder handled the key event
+*/
+- (BOOL)_processKeyboardUIKey:(CPEvent)anEvent
+{
+    var character = [anEvent charactersIgnoringModifiers],
+        uiKeys = [CPLeftArrowFunctionKey, CPRightArrowFunctionKey, CPUpArrowFunctionKey, CPDownArrowFunctionKey, CPPageUpFunctionKey, CPPageDownFunctionKey, CPEscapeFunctionKey];
+
+    if (![uiKeys containsObject:character])
+        return NO;
+
+    var selectors = [CPKeyBinding selectorsForKey:character modifierFlags:0];
+
+    if ([selectors count] <= 0)
+        return NO;
+
+    if (character !== CPEscapeFunctionKey)
+    {
+        var selector = [selectors objectAtIndex:0];
+        return [[self firstResponder] tryToPerform:selector with:self];
+    }
+    else
+    {
+        // Cocoa sends complete: for the escape key (in stead of the default cancelOperation:)
+        // This is also the only action that is not sent directly to the first responder, but through doCommandBySelector.
+        // The difference is that doCommandBySelector: will also send the action to the window and application delegates.
+        [[self firstResponder] doCommandBySelector:@selector(complete:)];
+    }
 }
 
 - (void)insertTab:(id)sender