Original work started for WPD and LGB, who wish to restrict flags
visibility in the UI based on admin_level. To support this change and
upcoming changes, `const.PERMS: string -> int` was created.
Potentially targetting a future design where Permissions is a proper
business object integrated with the User model; however, for now just
looking toward getting admin_level magic numbers centralized.
This commit applies PERMS to: create_hole, flags visibility in UI,
flag removal in UI & backend. Flag visibility in Comment & Submission
json_raw methods is unaffected to avoid needing a user object to
build the JSON.
Snakes
6ad935e12a