[Java] Validate maxValue on numInGroup against type to support range limits in RC4.

Author: mjpt777

sbe-tool/src/main/java/uk/co/real_logic/sbe/xml/CompositeType.java

@@ -173,6 +173,10 @@ else if (numInGroupType.primitiveType() != UINT8 && numInGroupType.primitiveType
  {
  XmlSchemaParser.handleWarning(node, "\"numInGroup\" should be UINT8 or UINT16");
  }
+ else
+ {
+ validateMaxValue(node, numInGroupType.primitiveType(), numInGroupType.maxValue());
+ }
  }
 
  /**