Watch Tower

Watch Towers are the protective towers of any city. They provide comfort to the citizens, and outposts to watch the countryside around them. Building requirements:
 * Name: Watch Tower
 * Tax Modifier: 2.5 (250 per object)
 * Size: 15*15
 * Protected by the server: Yes
 * Limit Per City: 4
 * A minimum height of 20 blocks
 * 5 sets of iron armor
 * 5 bows
 * 10 stacks of arrows
 * 5 diamond swords
 * Tower-like