[Java] Make sbeRewind use a fluent API to match C++ style.

Author: mikeb01

sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/java/JavaGenerator.java

@@ -2576,9 +2576,9 @@ private CharSequence generateDecoderFlyweightCode(final String className, final
  " headerDecoder.version());\n" +
  " }\n\n" +
 
- " public void sbeRewind()\n" +
+ " public " + className + " sbeRewind()\n" +
  " {\n" +
- " wrap(buffer, initialOffset, actingBlockLength, actingVersion);\n" +
+ " return wrap(buffer, initialOffset, actingBlockLength, actingVersion);\n" +
  " }\n\n";
 
  return generateFlyweightCode(DECODER, className, token, methods, readOnlyBuffer);