Blender Git Loki

* Two usability tweaks in adding objects, with user prefs

This changes the default behaviour in adding new objects, which has been
discussed for a long time, in person, on the funboard, and in the tracker,
and was agreed to be implemented during the 2.5 release cycle, so here it is.
They have been made default, with preferences to bring back old behaviour since
although people like myself still prefer the new default anyway, it will benefit
new users the most.

The preferences are in the 'Edit Methods' section, changing back to old behaviour
is as simple as a click of a button.

- Switch to edit mode preference

By default, now adding a new object doesn't automatically switch to edit mode.
Not only can this be annoying (most of the time when setting up scenes and models
I don't want to edit it straight away anyway), but it's a major hurdle in the learning
curve that new users have had to deal with at a very early stage.

Blender's different modes are an important part of understanding how the software works
and should have clear behaviour. The problem is that when a user selects something from
the add menu, he's not telling Blender to change modes, he wants to add an object.
But Blender then goes ahead and changes modes underneath him anyway, something that was
never explicitly asked for, something that's unrelated to the mental task at hand, and
fundamentally important to the operation of the software.

We observed plenty of people struggling with this during the training sessions that
we ran during Project Orange, and there's also no shortage of "why can't I select
other objects" questions on the forums.

- Aligned to View preference

Now by default, adding a new object doesn't rotate it so it's aligned facing the view,
but rather, it's remains unrotated in world space. This is something that's more of
a convenience issue (allowing people like me to stop the 'Add->Tab->Alt R dance),
but also makes things easier for new users, especially when doing things like rigging.

For a lot of tools in Blender, like curve deform, path cycling, constraints, it's necessary
for your objects' local axes to be aligned. This requirement isn't that obvious, and I've
had to debug rigs a few times from the animator in our studio, who has everything set up
correctly, but he just happened to be in a different vie at the time he added the object,
so they're misaligned and causing problems. Having all objects get created aligned to
worldspace, by default, makes a lot of these problems go away. It's much more understandable
when rotations are caused by something you've done explicitly, rather than as a side effect
of the software.

For convenience as well, most of the time, when I'm working in context and I decide I need a new object,
particularly working on production scenes that involve more than just one model, an Alt R
is almost always required after adding, since I don't want to have to disrupt the current
view of the scene by switching to top view, just to add an object. It's a bit arbitrary,
the view from which you want to look at your objects isn't usually the way you want them to
be looking at you.