Loot balancing overhaul and cleanup. Based on patch by fatherbushido, refs #4193.
Add missing loot entry to many new buildings that were added after r11524 and ships.
Give civic centers and wonders a significant amount.
Food related structures contain some food.
Temples somehow yielded 500 metal loot previously.
Remove experience point loot from non-defensive buildings.
Merge loot for cavalry and hero templates.
Swordsmen and sword cavalry loot 5 metal, slingers 5 stone, other units 5 wood.
Remove some duplicate Looter, MiniMap, Selectable and TrainingRestriction entries.
Remove pointless sentence "Special Building." from persian hall tooltip.