fix some tests
don't use sqlite in memory db for testing

using a db on filesystem is faster as pytest supports reusing the existing db, that way it's only slow on first run
oscar requirements added
added oscar settings
added some more oscar settings
enable the store
enable debug toolbar
forked partners app, use US strategy for pricing/tax
forked shipping app, added shipping types
added initial instruments fixture as a data migration
auto populate shipping countries table
update sqlparse