Add extract_archive(archive, target) function
Implement Task "extract"
Add subpath (e.g. 01.135) to <ESPAS_Result><name>
Make time period for script running time more human readable
Merge branch 'master' of github.com:GFZ/isdc-espas-converter

* 'master' of github.com:GFZ/isdc-espas-converter:
  Fix wrong linebreak for command line output