Add Gauss unit to MagneticField (#861)

Author: krwq

Common/UnitDefinitions/MagneticField.json

@@ -14,13 +14,25 @@
       "PluralName": "Teslas",
       "FromUnitToBaseFunc": "x",
       "FromBaseToUnitFunc": "x",
-	  "Prefixes": [ "Nano", "Micro", "Milli" ],
+	    "Prefixes": [ "Nano", "Micro", "Milli" ],
       "Localization": [
         {
           "Culture": "en-US",
           "Abbreviations": [ "T" ]
         }
       ]
+    },
+    {
+      "SingularName": "Gauss",
+      "PluralName": "Gausses",
+      "FromUnitToBaseFunc": "x/1e4",
+      "FromBaseToUnitFunc": "x*1e4",
+      "Localization": [
+        {
+          "Culture": "en-US",
+          "Abbreviations": [ "G" ]
+        }
+      ]
     }
   ]
 }

UnitsNet.NumberExtensions.Tests/GeneratedCode/NumberToMagneticFieldExtensionsTest.g.cs

@@ -32,5 +32,6 @@ public class MagneticFieldTests : MagneticFieldTestsBase
         protected override double NanoteslasInOneTesla => 1e9;
         protected override double MicroteslasInOneTesla => 1e6;
         protected override double MilliteslasInOneTesla => 1e3;
+        protected override double GaussesInOneTesla => 1e4;
     }
 }