improve strings for traffic signal fields (#456)

data/fields/button_operated.json

@@ -1,5 +1,5 @@
 {
     "key": "button_operated",
     "type": "check",
-    "label": "Button Operated"
+    "label": "Call Button"
 }

data/fields/traffic_signals/countdown.json

@@ -1,5 +1,5 @@
 {
     "key": "traffic_signals:countdown",
     "type": "check",
-    "label": "Countdown"
+    "label": "Countdown Timer"
 }

data/fields/traffic_signals/sound.json

@@ -7,12 +7,12 @@
             "yes": "Yes",
             "no": "No",
             "locate": {
-                "title": "Locate",
-                "description": "There is only a signal to find the pole"
+                "title": "Call Button Locator",
+                "description": "There is a signal only for finding the call button"
             },
             "walk": {
-                "title": "Locate",
-                "description": "here is only the signal when walking is allowed"
+                "title": "Walk Indicator",
+                "description": "There is only a signal when walking is allowed"
             }
         }
     },

data/presets/highway/traffic_signals.json

@@ -10,6 +10,9 @@
         "traffic_signals",
         "traffic_signals/direction"
     ],
+    "moreFields": [
+        "traffic_signals/countdown"
+    ],
     "terms": [
         "light",
         "stoplight",