This patch tries to implement support for the cursor orientation on object creation.

Instead of a single toggle with the view_align property, I have added an enum propery which holds the cursor as well.
So, now the user can choose between the Global/View/Cursor options.

I left the view_align property alive, and made it so that it just sets the enum property - doing so should keep the python api untouched. None
the less it's a bit ugly to have two sameish options in there.. not sure what to do about it.

To my surprise much of this is implemented a second time in python. After looking a bit into it, it seems like it needs similar changes like on the C side. Probably best adressed in a different patch.

Notes:
in the original source there is this block on line 361:

*is_view_aligned = (U.flag & USER_ADD_VIEWALIGNED) != 0;

I did not understand what this is doing, so this surely needs someone to check.