Change fluid importer behavior

[hjae78]

Issue description: In GregTech there are machines with several fluid output slots, the fluid importer can only drain from the first non-empty fluid slot.

What happens: The importer on fluid mode only imports fluids from the first slot.

What you expected to happen: That the importer can import fluid from any slot.

Steps to reproduce:

1. Using GTCE run any recipe that results in 2 or more fluids.
2. Try to import a fluid that isn't in the first slot from the left.

Basically the issue is here. It should loop over the fluid tank properties like here.

[tth05]

Thanks for the hint!

[hjae78]

Thank you for the quick fix! The mod I manage, Gregicality, actually has some more coremod fixes for Refined Storage. Refined Storage can't shift click GTCE tools into crafting grid. This is our coremod for RS.

[tth05]

I'm not exactly sure what those hooks are supposed to accomplish, but inserting and extracting works for me with meta items.