Generator: Renamed cBiomeGenerator's Initialize() to InitializeBiomeGen().

This will allow initializing generators that implement both cBiomeGenerator and other generators.
Added GetIniItemSet() function.

It reads a block / item description from the specified INI file value and returns as cItem; stores and uses the default if value doesn't exist.
CompoGen and HeiGen read their settings in their respective Initialize() functions.
Updated BiomeVisualiser to compile again.
Fixed second logger constructor.
BiomeVisualiser: fixed crash at shutdown caused by bad logging
APIDump: Hook notes are linkified.
APIDump: Documented OnBlockToPickups.
APIDump: Added the possibility of extra code examples for hooks.
APIDump: Added an OnBlockToPickups() code example.
APIDump: Added pretty-printing to code examples.
Mob spawning changes

Added EnderDragon, Blaze and Horse spawning.
Added extra line
Added more ghast spawning probability
Fixed and exported cWorld:QueueTask().

This implements #220.
Merge pull request #224 from tonibm19/patch-7

Added Horses, Blazes and EnderDragons spawning.