[entropy.db] use super() instead of class.__init__()
[entropy.db.sql] definitely fix the cursor object wrapping
[tests] db: fix test_libs_download
[entropy.client] add support for multiple "repo =" repository parameters

This improves the availability when one or more repository database
mirrors are down.
[tests] security: create temporary directory using TMPDIR or, if unset, $PWD
[equo] rewrite "equo repo add" command line interface, looks much better now