The time it takes to chop down a tree is calculated by the amount of blocks/logs that tree contains.
Also, the tools used affect the time it takes to break a tree. (mentioned in #7)
Currently, it is possible to chop down ENORMOUS trees just by breaking a single block (like Biomes O' Plenty trees), which is really OP.

P.S: You managed to implement durability calculations, cool!

This feature is almost ready for the next release