Add theme for each of the 4 Elements

[garykac]

Add more rigid theme for each Element type and have the spells for each Element focus on that type.

• Air - Fast physical movement, Defense
• Earth - Physical Defense, Attack
• Fire - Attack
• Water - Magical Movement (Astral plane), Healing, Defense

[garykac]

• Air - Movement
• Fire - Attack
• Water - Defense
• Earth - Anchoring/Defense