fix hub bugs, add channel role permission endpoints

Covers: snake_case param renames, mutex RLock/Unlock mismatches, user.Hubs keyed by hub.Id, hub color using new_name, DELETE params sent as query, delete(target.Hubs, hub.Id), root/member role Id swap, and the three new PATCH
  /hub/channel/roles/* handlers.

packages/httpRequest/files.go

@@ -153,9 +153,9 @@ func HandleGetUserAvatar(response http.ResponseWriter, request *http.Request) {
 		return
 	}
 
-	targetId, err := convertions.StringToUuid(request.URL.Query().Get("userid"))
+	targetId, err := convertions.StringToUuid(request.URL.Query().Get("user_id"))
 	if err != nil {
-		http.Error(response, "invalid userid", http.StatusBadRequest)
+		http.Error(response, "invalid user_id", http.StatusBadRequest)
 		return
 	}
 
@@ -274,9 +274,9 @@ func HandleGetUserProfileBg(response http.ResponseWriter, request *http.Request)
 		return
 	}
 
-	targetId, err := convertions.StringToUuid(request.URL.Query().Get("userid"))
+	targetId, err := convertions.StringToUuid(request.URL.Query().Get("user_id"))
 	if err != nil {
-		http.Error(response, "invalid userid", http.StatusBadRequest)
+		http.Error(response, "invalid user_id", http.StatusBadRequest)
 		return
 	}