This change pulls as much pagination logic out of the database
implementation as possible. Database implementations should now be able
to marshal whatever state they need into opaque tokens with the
utilities in the pagination package.
This change refactors a lot of the code dealing with pagination so that
fernet implementation details do not leak.
- Deletes database/pgsql/token
- Introduces a pagination package
- Renames idPageNumber to Page and add a constructor and method.
This puts config in its relevant location and moves functions around
loading config files into the main package.
As a side effect of removing cyclic imports for the API config, the
context library is no longer used.
