PeteOpenGL2Tweak 2.3

Deposterize filter - useful for games with heavy dithering like Silent Hill.
Fixes & optimizations in Texture Cache.
Slice option replaced with BatchSize for more even parallel workload.
Changed some default settings.

About BatchSize:
This value represents number of texels (texture pixels) to be processed at once ie. higher value - less parallel processing, lower value - more parallel processing.
So old slice option was number of batches, and new option is a size of single batch.
Making batch size constant and calculating slice sizes at run-time make workload more even because different textures now have different slice count.