Document and extend Effect Types

[jdrueckert]

Once the extraction of effects into this module is complete, we can order, document and extend what we have.

Effects can be classified by different dimensions, including but not limited to their amount of damage (including no damage at all), the impairment they cause (e.g. slow-down, stun, enlargement, blurred vision, blocking abilities etc.), their target behaviour (e.g. single-target, multi-target, area of effect, chaining) or their time-wise development (e.g. instant, permanent, temporary, delayed).

Depends on Terasology/Towers#4