Thorough testing of inserting and fetching data

Tested inserting and fetching data in the database. Nothing broke or
crashed.

Insertion command for creating a new player has been built.
Further testing of database functionality

Testing showed these things:
1. The local database clears all entries when building/rebuilding the
project.
2. Running the program normally in the ide runs through debug, which
always rebuilds the program before starting the run.
3. Testing showed the database was indeed saving by running without
debug.
(Testing steps went running w/o debug and saving to database. Closed the
program then starting it again w/o debug this time only fetching the
desired data. Data was retrieved properly without the need for
reinsertion)

Player selection functionality has been put into a method. (also
insertion functionality has its own method)