Basic initial implementation of GETSIZE/DELETEDATA.

LittleBigPlanet uses these.  It seems happier with these working,
although it goes on to call MAKEDATA.

Also seems to make some other games happier.

GETSIZE not heavily tested yet.
Add a resched delay to sceUtilitySavedataUpdate().

Looks like this really happens.  Most games don't seem to care.
Merge pull request #1016 from unknownbrackets/savedata

Implement some of savedata GETSIZE and DELETEDATA