allow publishing of local or remote .zip files
refactored cache module

- moved loading of catalog and updates into registry module
- split various methods for easier unit testing
removed superfluous variable declarations
added methods for use in unit tests, replaced setConfig with reset
fixed typo
extended registry tests using a mocked webserver

registry tests mostly just test the parameters and format sent to rpr, they don't mimick rpr's response.
the mocked webserver allows using stick for route configuration, params parsing etc. within unit tests.
added tests for catalog cache
minor fix in help output
simplified extractFile using ringo's zip module, added unit tests for compress module