Blender Git Loki

Change movie cache to use vectors instead of lists.

Runtime costs were horrible. On gooseberry in some sequencer edits using
proxies of small size, a cache with about 2000 elements would slow to
about 6 fps once cache was full and system tried to find smallest
element available.

There are still improvements to be done here, like requesting a number
of good candidates to avoid rerunnung through the list, or even using
some heap or ring buffer scheme to sort data, but nothing suits all
needs so for now that should bring the cache back to usable state (25fps
here at the studio)