2.5: Lists for vertex groups, shape keys, uvs, vertex colors.

2.5: Lists for vertex groups, shape keys, uvs, vertex colors.

RNA
* Added the relevant active_*_index properties, with proper
  get/set/range, updates and notifiers.
* Context.tool_settings.
* ToolSettings.vertex_group_weight.

Operators
* MESH_OT_uv_texture_add/remove
* MESH_OT_vertex_color_add/remove
* MESH_OT_sticky_add/remove
* OBJECT_OT_vertex_group_add/remove/assign/remove_from/
  select/deselect/copy/copy_to_linked
* OBJECT_OT_shape_key_add/remove

UI
* Some updates and cleanups in list template code.

Known issue: when going in & out of editmode, uv textures and vertex
colors dissappear. I thought me->edit_mesh would be NULL when not in
edit mode but it is not?