Storage settings with type safety

[barrymun]

• builds on #27
• making the settings type safe and assigning to an interface to avoid confusion
• using function overloading on getStorageValue so that it can be used in multiple different ways with different params and different return types
• removing a lot of console logs
• wip, still testing

example when getting:

example when setting:

[barrymun]

@chris-mosley thanks for merging in #27, this one should be ready for merge after testing as well. i've made a few changes:

• added function overloading for getStorageValue so that it can be used more easily
• no longer required to pass undefined to getStorageValue if not specifying and of the StorageSettings keys (like abfFirstRun, etc.)
• removed some console logs as it was getting a bit cluttered (we can add them back in if required but wanted to clean it up a little)
• debugMode renamed to useDebugMode for consistency (matches pattern set by usePersonalBlock)
• removed some unused functions that were commented