Added Timber-Modifier
- Timber cuts down trees in one go
- can't be combined with Power
- Tree is defined as:
- has grass under log and leaves over log

Shovels now get Exp when creating pathways
Poisonous now can be applied on the Axe
Power now should not destroy tools with low durability anymore

Added useful comments to code (removed less useful ones)
Code-optimization and improvement
Increased version number from a8 to a9