Hide empty sections from template creation

Active tabs are shown in creation by template dialog (and in public form as well since it uses the same template class) even if the tab has no needed attributes.

This results in a buggy-looking empty section in the form, which should not be shown.

mentioned in merge request !409

By Côme Chilliet on 2018-10-01T12:46:16 (imported from GitLab)

mentioned in commit 6ef556be

By Côme Chilliet on 2018-10-01T12:47:38 (imported from GitLab)

added 30m of time spent at 2018-10-01

By Côme Chilliet on 2018-10-01T13:33:58 (imported from GitLab)

added To Be Tested label

By Côme Chilliet on 2018-10-01T13:34:13 (imported from GitLab)

closed

By Côme Chilliet on 2018-10-02T09:28:23 (imported from GitLab)

added 15m of time spent at 2018-10-02

By Côme Chilliet on 2018-10-02T09:28:24 (imported from GitLab)

added Fixed and removed To Be Tested labels

By Côme Chilliet on 2018-10-02T09:28:24 (imported from GitLab)

added templates label