Updated readme with new contributor's guide #dev
Making coke from wood no longer creates ash.

Wood blocks/planks to coke no longer has a 20% chance of producing ash.

Instead, the player has to choose whether they want coke or ash from planks.
(Similar the to wood oven.)

Players may also burn a wood log to 3 ash.

Split commit from 7be2d976d21e6ade4ed9b15b3d8af4780e6aaf10

GH #101
Rebalance: Medicine now makes 3 potions from 1 stack of plants

Previously this was 5 potions from two stacks.

Split commit from 7be2d976d21e6ade4ed9b15b3d8af4780e6aaf10

GH #101
Clean-up of boneyard reactions and typo fixes

* Fixed indentation
* Changed instances of 'bone bone' to 'bone'
* Removed duplicate names in some reactions.
Merge branch 'gold' into orc_rebalance

* gold:
  Clean-up of boneyard reactions and typo fixes
  Rebalance: Medicine now makes 3 potions from 1 stack of plants
  Making coke from wood no longer creates ash.
  Updated readme with new contributor's guide #dev
Orcs now have comprable boneyard products to dwarves.

Added:
    * Coffins
    * Hatch covers
    * Slabs
    * Statues
    * Jugs
    * Candelabras, braziers and fireplaces
    * Mortar and pestle
    * Nest boxes and hives
    * Large pots

Removed:
    * Bone-rattles

Fixes #107