Instead of calling an operator I just call `collection.new()`. Moving the
code into a separate function also simplifies it. In its new form there is
also no undefined behaviour when me.vertex_colors is non-empty but without
active layer.
- normalize → average the vector: the vector isn't normalized here, because
it doesn't necessarily becomes unit length. Instead, the sum is converted
to an average vector.
- angle is the acos()…: the dot product between the vertex normal and the
average direction of the connected vertices is computed, and not the
opposite.
- The initial `con` list was discarded immediately and replaced by a new
list.
- File didn't end with a newline.
ui/ --> startup/bl_ui
op/ --> startup/bl_operators
scripts/startup/ is now the only auto-loading script dir which gives some speedup for blender loading too.
~/.blender/2.56/scripts/startup works for auto-loading scripts too.
