[PLT-5864] Move teammate name display setting to the System Console (#6681)

* move teammate name display setting to the system console

* update all the likes of TeammateNameDisplay names

* fix gofmt error

* rebase and fix conflict

webapp/i18n/en.json

@@ -875,8 +875,13 @@
   "admin.team.siteNameDescription": "Name of service shown in login screens and UI.",
   "admin.team.siteNameExample": "E.g.: \"Mattermost\"",
   "admin.team.siteNameTitle": "Site Name:",
+  "admin.team.showFullname": "Show first and last name (default)",
+  "admin.team.showNickname": "Show nickname if one exists, otherwise show first and last name",
+  "admin.team.showUsername": "Show username",
   "admin.team.teamCreationDescription": "When false, only System Administrators can create teams.",
   "admin.team.teamCreationTitle": "Enable Team Creation: ",
+  "admin.team.teammateNameDisplay": "Teammate Name Display:",
+  "admin.team.teammateNameDisplayDesc": "Set how to display users' names in posts and the Direct Messages list.",
   "admin.team.upload": "Upload",
   "admin.team.uploadDesc": "Customize your user experience by adding a custom image to your login screen. Recommended maximum image size is less than 2 MB.",
   "admin.team.uploaded": "Uploaded!",
@@ -2188,7 +2193,7 @@
   "user.settings.display.showFullname": "Show first and last name",
   "user.settings.display.showNickname": "Show nickname if one exists, otherwise show first and last name",
   "user.settings.display.showUsername": "Show username (default)",
-  "user.settings.display.teammateDisplay": "Teammate Name Display",
+  "user.settings.display.teammateNameDisplay": "Teammate Name Display",
   "user.settings.display.theme.applyToAllTeams": "Apply new theme to all my teams",
   "user.settings.display.theme.customTheme": "Custom Theme",
   "user.settings.display.theme.describe": "Open to manage your theme",