refactor: popups -> tooltips

src/locales/en.json

@@ -182,7 +182,8 @@
       "addons": "ADDITIONAL PROGRAMS",
       "blockades": "BLOCK SIGNALLING",
       "status": "ONLINE STATUS",
-      "timetables": "ACTIVE TIMETABLES"
+      "timetables": "ACTIVE TIMETABLES",
+      "spawns": "OPEN SPAWNS"
     },
 
     "all-available": "ALL AVAILABLE",
@@ -242,6 +243,7 @@
       "routes-2t-cat": "MIN. CATENARY DOUBLE TRACK ROUTES",
       "routes-2t-other": "MIN. OTHER DOUBLE TRACK ROUTES"
     },
+
     "authors-search": "SEARCH BY AUTHOR NAME (other filters apply):",
     "authors-placeholder": "Enter the author nickname...",
     "authors-button-title": "Search",