#8 added frame property to QMIcon
#8 using mouse-track loop approach in QMIconGridView, because:
1. add an icon
2. right-click on the freshly added icon and release the mouse (mouse-up)
3. -mouseUp: of QMIconGridView is fired again
#8 added a context menu with
- delete icon
- delete all icons
#8 localized "delete icon"
#8 tests for -menuForEvent:
#8 minor refactoring in -menuForEvent:
#8 displaying unsupported icon when the hit icon is not (yet) supported
 #8 updating qkit

To use the block-based NSMenuItem
#8 using block for NSMenuItem (yet dummy)
#8 added dummy delete icon methods for the data source and document
fixed also the test for QMIconGridView
#8 implemented the test for the data source
#8 implemented the test for the document
#8 implemented test for the delete icon menu action
#8 implemented and tested delete all icons for mindmap view

document and datasource are tbd
#8 implemented and tested datasource
#8 implemented and tested document
#8 slightly modified context menu display behavior

- always showing the menu
- disabling appropriately
#8 updating qkit
#8 refactored -menuForEvent:
#8 deletion of icons works