Optimization: moved functions to Application

Need to create smaller subclasses to divide the task of deck management,
database management, etc.
Optimization: moved create/delete to FileManager
Optimization: created DB intent service
Optimization: reorganized into packages/+1/-1/x

Added functionality to +1 card, -1 card, and clear field buttons. Next
step is to organize output AND stop user from accessing OPENACTIVITY
until DB finishes loading.