smoketest: Use sudo to install packages
smoketest: Add SUSE support
smoketest: Style fixes
Use new validation API in validate_proposal_after_save
Use new find_dep_proposal helper
Merge pull request #128 from vuntz/validation

Use new helpers to create/validate proposals
Merge pull request #127 from vuntz/smoketest-fixes

Some fixes for the new smoketest script (mostly style)