Blender Git Loki

NLA SoC: Channel ordering change

In response to user-feedback, I've changed the order in which channels appear. Now, the channel ordering is:

- Object/AnimData block
-- Active Action
-- Last NLA Track
..
..
-- First NLA Track

It is important to note several things still:
1) Active action is applied AFTER the NLA Tracks have been evaluated, not before
2) In this new order, the tracks+active action are shown in the evaluation-stack order, i.e. first thing applied is at the bottom, last is at the top.

As a result, I've switched the view-orientation back so that it works the same way as for DopeSheet/Graph editors (i.e. expands downwards not upwards). This may cause problems loading files saved with older builds of this branch. There are still some lingering problems due to this change which I'll fix in due course.