Improve compatibility by adding type to float properties in GremlinGr…

…oovy (#220)

- `.property('float_prop',1.4)` → `.property('float_prop', 1.4d)`
- JanusGraph/janusgraph#487

Signed-off-by: Dwitry dwitry@users.noreply.github.com

translation/src/main/java/org/opencypher/gremlin/translation/groovy/StringTranslationUtils.java

@@ -59,6 +59,9 @@ public static String toLiteral(Object argument) {
         if (argument instanceof String) {
             return toStringLiteral((String) argument);
         }
+        if (argument instanceof Double || argument instanceof Float) {
+            return argument.toString() + "d";
+        }
         if (argument == null) {
             return "null";
         }