Default manager export

[pdspicer]

Added a default storage manager to main export, as well as a config() method for the StorageManager class in order to reconfigure the default storage manager without reinstantiating. This allows callers to do storage manager setup once at application start and reuse the same instances without needing to require() a separate file where a configured StorageManager has been set up. This is a similar pattern to how popular database and logging libraries export default containers for connections or loggers. Seeing as storage drivers fall under a similar class of reusability throughout an application, use of this pattern seems appropriate in this library.

Note: I submitted this to slynova-org as well, but that repo doesn't seem to be particularly active, and seeing as you've put all this work into actually making some active improvements I figured I'd just try here instead of publishing yet another version of this library.

Additional note: I did some incredibly minor cleanup both for eslint as well as for the actual build (needed to add 'dom' to the lib in tsconfig), don't know if this is something that has changed in the last two months or what.. regardless its just a type checking thing, don't think it actually impacts any of the output.