Fixed #106. POSTing to scans requires user.

We want to display the user started the scan in the frontend, and we
have to add user (oriignally called owner) in the POST and have
summary_scan(..) to return 'meta' as part of the summary.
Fixes #112 The plans API should not return plugin descriptors
Merge pull request #108 from yeukhon/issue106

Issue106
Removed test_api.py. I think it got accidentally added back after splitting up the tests.