Added a test that stores a long in a JsonValue

JsonGenerator/JsonValue.cpp

@@ -14,13 +14,23 @@ size_t JsonValue::printBoolTo(Print& p) const
 
 size_t JsonValue::printDoubleTo(Print& p) const
 {
-    char tmp[16];
+    char tmp[32];
 
     sprintf(tmp, "%lg", content.asDouble);
 
     return p.write(tmp);
 }
 
+size_t JsonValue::printLongTo(Print& p) const
+{
+    char tmp[32];
+
+    sprintf(tmp, "%ld", content.asLong);
+
+    return p.write(tmp);
+}
+
+
 size_t JsonValue::printPrintableTo(Print& p) const
 {
     if (content.asPrintable)