added field hostname to model and to forms (DC|BO)(add|edit) plus test
added readonly hostname field to bulkedit asset
fixed test test_bulk_edit_max_items_at_once
added field hostname to search; tests fails
added tests for searching hostname field & flake8 fixes
added name to api & migration file
changed 'name' to hostname' (API)
changed *hostname* field widget to SimpleReadOnlyWidget
Merge pull request #330 from xliiv/hostname-field

Hostname field
Merge branch 'develop' into 308-xls-update-error