Controlled Burn

This version and up will require Fantastic Lib

For github #5; setting a block's flammability to a negative value makes it behave like netherrack as far as fire goes

For github #6; config for LOS requirement on fire spread (does not include fire creation from lava blocks)

Likely general compat improvement

Config for tick delay randomization

Re-added "requires MC restart" on block-specific config. Specifically, it would not update correctly if an entry for a block existed in the config and then was removed (until after restart).  Otherwise it doesn't *actually* require restart