Update 1.0.3.7 bug fixes and Archmage perk

This is just a quick update to fix a few bugs, but as people are having to download a new update so quickly i thought i'd implement the next upgraded perk:

The Archmage character still has his original perk, allowing him to receive a free empire spell at the end of each year. But on top of this he is now able to construct a grand library in each city he owns. Grand libraries offer the archmage even more ways to receive spells, each grand library has a small chance of generating a new spell for its owner every turn.

As well as granting a chance at a free spell each turn grand libraries also produce mana, allowing the archmage to cast more spells and sustain more magical creatures than other characters.