Merge branch 'develop'; major refactoring complete (read more)

Streamlined the build process, including:
* Restructured the common directory
* Moved the client's scenes up one level
* Removed the unused DEBUG flag, added the GRAPHICS flag
* Moved the server's data structures to the common/gameplay directory
* Data structures are now shared by the client and server

Other changes include:
* Created the StatisticData structure
* Removed the server's static variables
* Some progress on basic combat system framework
* CharacterData now has methods (derived from the delete PlayerCharacter)
* Client-side tables are now shared between the scenes
* Refactored UDPNetworkUtility, tying it to SerialPacket
* Added new structures to SerialPacket, and serialization
* Renamed and rearranged the SQL tables
* Solved a few other TODO tags
* Updated the license headers
Committing todo.txt