Blender Git Loki

Small fixes for UI;

- Add UV Sphere now aligns with view, as do all primitives
- Small drawing error in edges between blender areas (black lines were 2
pixels too short)
- Replaced the heuristics in opening sublevel menus, to be less frustrating.
It now keeps sublevel open while mouse moves within the triangle defined
by original mouse location (before moving) and the closest vertical edge
of the new sub menu. Works nice for toolbox and pulldowns.