Version 0.6.0

I've been busy with other stuff and let the Christmas version stay up for too long :)

In addition to removing Christmas content, the current version has some balancing updates:

• Level 3 enemies spawn in higher numbers
• Necromancer was nerfed even further (spawns 15% of enemies, down from 20%)
• Giant Magnet was nerfed (cannot summon Titans anymore)
• Some tribe-specific relics got a buff:
  • Mech Tech gives Mechs +100 hp (up from +50)
  • Commander gives Humans +2 defense (up from +1)
  • Warmonger gives Orcs +5 attack (up from +4)
  • Boiling Blood gives Demons +8 attack (up from +5)

This is likely the final version of this game for a long while. Cheers!