Add a convenience helper to load a file oneshot.
Dynamically manage PPGe images so 50+ are okay.

Otherwise, we try to allocate all at once and could run out of ram.

Should fix #2242.
Use ReadEntireFile() a few more places.

This fixes one or two minor memory leaks.
Merge pull request #4756 from unknownbrackets/savedata

Load savedata images dynamically, cleanup oneshot file reads
Use multiple threads if available for softgpu.

VIVA OVERHEAD.  But it's actually generally faster this way, even with
only 2 cores running (but not a huge improvement then.)

On an i7, this improves things ~2.5x with 8 cores.
Optimize out some clear mode checks.

Since it's really common and the rasterizer is slow for large draws.
Merge pull request #4758 from unknownbrackets/softgpu2

Use multiple threads if available for softgpu.
Fix double free when saving.
As if softgpu wasn't slow enough already, implement bilinear filtering.
Blackberry: Improve packaging.
Merge branch 'master' of http://github.com/hrydgard/ppsspp