* Measure Panel - Version 0.7.12

* Moved setting of properties to callback function (it is bad practise to set it in the draw code).
* Fixed distance calculation of parented objects.
* API change: add_modal_handler -> modal_handler_add
* Regression: I had to disable area display for selection with more than 2 meshes (for now, still searching for a nice solution).
* Fixed Local/Global vert-loc calculations in EditMode.