Blender Git Loki

Addons:
Some code changes:

* Every Add-On now needs a dictionary with several infos, which are then displayed in the Blender UI and/or are used internally.

Example:
bl_addon_info = {'name': 'Measure panel',
'author': 'Buerbaum Martin (Pontiac)',
'version': '0.6.3',
'blender': '2.5.2',
'location': 'View3D > Properties > Measure',
'url': 'http://wiki.blender.org/index.php/Extensions:2.5/Py/Scripts/Panel_Measure',
'category' : 'UI'}

Unfinished/Not working yet
* The 'blender' tag is compared with the internal version number, it raises an error if the add-on was written for a newer Blender version.
* The 'category' tag will be added to the filter, so the add-ons can be searched/filtered.