Initial commit for GameDBInteractor.
Instrad of an inheritance relationship, I chose to create a composition
relationship between the GameDBInteractor and the DatabaseInteractor.
This way, the DatabaseInteractor allows multiple instances of itself,
useful if we ever need to connect to multiple databases, and the
GameDBInteractor (and anything that inherits from it) may have all
static methods. Or, that is to say, the child may be static while the
parent permits multiple instances.