Fixed bug report #432870: applied some patches from thread and additional/reworked fixes.
Everything mentioned should be fixed - also attributes with seperate SKU and no stock, no longer needs an empty stock entry in stock table for attributes to be shown (changed sql to use left join).
works for me - pls. test and tell me if I've missed a fix.
Fixes two more bugs reported by TwistedLincoln:
- JS filtering didn't work properly if an attribute was changed a second time.
- Disabled stock level check when not in full node view.