* General:
** Move shape and tool to plugins/
* Loading/saving
** Add support for entity elements
** Refactor attribute manager:
*** It needs to be DOM aware to support complex attribute management (e.g. font-style attribute handling)
*** Detection and proper handling of invalid attributes and values.
*** Implement inheritsAttribute() method in every element class
** make load and save working for every element, and update test suite
** add defaultAttributevalues to mstyle
** correct mathspace parsing in operator element.
* Painting
** implement rendering in all token elements
* UI/Tool
** Implement the new tool widget
** Implement insertText completly -> some stuff is still missing for glyph elements

mid term ( potential prerelease ) goals:
- create template files - decide what kind of templates should be in place
- add attribute caching as member variables in elements so that paint()
  does not need a AttributeManager

long term goals:
- iron the loading process out so that it won't crash on errors and report them
