make db filds more explicit
fixed file tree (don't kow how)

fixed the file tree hierarchy not working like it should
the fix is really strange though, it only worked before due to
a typo in the old code. I removed the line that I had "fixed" and
now it works as it did before.

Added option to choose the name of the database file (defaults to :memory:)

added sorter.py file for debug purposes