Description of problem:
When a template is locked, its inputs can't be edited in WebUI but they can be edited through CLI and API.

Steps to Reproduce:
0. Have some locked template
1. $ hammer template-input create --template-id <id> --input-type user --name <newname>
Template input created

Actual results:
Template input added to the template

Expected results:
I shouldn't be able to edit anything in the template

Additional info:
This is probably because template-input is handled as a different entity than the template itself