Configuration and more growth rate parameters

Added configuration (YML)

Growth rates are now expressed as fractions (of normal growth rate) and can benefit from sunlight, being exposed to the surface, and being "fertilized" with blocks beneath them, along with the biome. No glowstone check yet, but that could be added easily. The user can check the growth rate of a plant by hitting the ground with that plant's product (hitting an animal with a stick does the same).

It doesn't recognize data values yet, so when interrogating the growth rate, the different saplings are not differentiated, and all dyes are assumed to be cocoa beans.