Tread Heading events with undefined Reference as True

Source is a yacht with a Cetrek 340 Chartnav, a 730 Pilot, and a 930580
Magnetic compass, feeding into Cetrek 2900 instruments.

Author: stefanor

pgns/127250.js

@@ -14,8 +14,10 @@ module.exports = [
     node: 'navigation.headingTrue',
     filter: function (n2k) {
       return (
-        n2k.fields['Reference'] === 'True' &&
-        typeof n2k.fields['Heading'] !== 'undefined'
+        typeof n2k.fields['Heading'] !== 'undefined' && (
+          n2k.fields['Reference'] === 'True' ||
+          typeof n2k.fields['Reference'] === 'undefined'
+        )
       )
     }
   },

test/127250_heading.js

@@ -52,4 +52,17 @@ describe('127250 Heading', function () {
     )
     // tree.should.be.validSignalKVesselIgnoringIdentity
   })
+
+  it('Cetrek sentence converts', function () {
+    var tree = require('./testMapper').toNested(
+      JSON.parse(
+        '{"canId":233902663,"prio":3,"src":71,"dst":255,"pgn":127250,"timestamp":"2022-12-11T14:48:31.783Z","fields":{"Heading":6.2657},"description":"Vessel Heading"}'
+      )
+    )
+    tree.should.have.with.nested.property(
+      'navigation.headingTrue.value',
+      6.2657
+    )
+    tree.should.be.validSignalKVesselIgnoringIdentity
+  })
 })