More registry fixes (1.10.2)

• Make sure hammer recipes respect "meta_ignored"
• Fix meta-specific block inputs not working in sieve recipes (identical to the hammer fix)
• Improve barrel recipe management: default recipes can be disabled (hurray!), and recipes can be changed at runtime with the usual "/enoreg reload" command. Lucky for me, the functionality was already there. I just added the forgotten function calls.

Unofficial bugfix (1.10.2)

• Fix block meta (technically blockstate id) being ignored in hammer recipes (Jozufozu#151). So, now you can override the default ore block recipes as well as differentiate between other blocks which share the same id, such as wood or stained glass.
• Possible fix for NPE on crucible tick (Jozufozu#152). I was able to produce a crash by going into the save file and removing the item from the crucible tile entity, and built a fix around that.