Implements `NumberOfDocks` and `DockingOffset#` for BuildingTypes.

[CCHyper]

Closes #786

This pull request implements NumberOfDocks and DockingOffset# for BuildingTypes.

NOTE1: This feature currently only applies to the following BuildingTypes; - Structures with Helipad=yes, where DockingOffset0 adjusts the docking position for aircraft. A NumberOfDocks value greater than 1 has no additional effect at this time. - Structures with Refinery=yes or Weeder=yes, where DockingOffset0 adjusts the docking position for the harvester. A NumberOfDocks value greater than 1 has no additional effect.

NOTE2: The default docking coord is offset from the center of the building for the following BuildingTypes; - Refinery=yes is offset by 128 leptons on the x-axis. - Weeder=yes is offset by 512 leptons on the x-axis, and 256 leptons on the y-axis

---

[BuildingType] (RULES.INI) NumberOfDocks=<integer> - The number of docking locations this building has. Defaults to 1 for buildings with Helipad=yes, and 0 for all other buildings.

[Image] (ART.INI) DockingOffset#=<X,Y,Z> - The coord offset from the center of the building for the respective docking location. This list must contain the same number of entries as defined by NumberOfDocks, with # being replaced by the docking position starting from zero. Each entry defaults to 0,0,0.