Changing the way we mattermost handles URLs. team.domain.com becomes domain.com/team.

Renaming team.Name to team.DisplayName and team.Domain to team.Name.
So: team.Name -> url safe name. team.DisplayName -> nice name for users

api/templates/email_change_subject.html

@@ -1 +1 @@
-{{define "email_change_subject"}}You updated your email for {{.Props.TeamName}} on {{ .Props.Domain }}{{end}}
+{{define "email_change_subject"}}You updated your email for {{.Props.TeamDisplayName}} on {{ .Props.Domain }}{{end}}