Cannot set groupID or userID for protected tag via API

Release notes

Added allowed_to_create param to protected_tags API.

Problem to solve

Currently there's no way to set a group_id as the create_access_level for the protected tags API. We only allow a specific group of users to create v* tags but there's no way to programatically set this. This means we have to manually go in and change this setting for hundreds of projects.

Proposal

Add an allowed_to_create hash optional param to POST /projects/:id/protected_tags much like the allowed_to_* params in the protect branch API.