Improve list_jobs to enable searching in several job_settings

 * It was impossible to search on 'iso' and 'build' in the same call: fixed.
 * Added distri, version and flavor
Buildview moved to tests_overview (with some enhancements)

 * It considers only 'current' jobs
 * It displays a summary
 * Distri and version are also required
 * Tests included
Tidying up the code
Merge pull request #33 from ancorgs/revamp_buildview

Buildview moved to tests_overview (with some enhancements)