Character Updates

Updated Player to contain the shared methods for leveling up. Changed
level up to private and is called whenever experience is gained. Added
Base Attack Bonus strategy and Saving Throws strategy. An Enum for
saving throws. 11 Character classes with their constructors. Attack
methods still need to be coded.
Build Errors

Fix build errors / Learned more about how accessors in C# work
Added HP and Mana manipulation methods to Entity, Fixed broken
Polymorphism in Player
merge conflicts
Merge pull request #14 from EWUTinfoilHats/EntityFixes

Entity fixes