ENH: simplify stream construction

- with IOstreamOption there are no cases where we need to construct
  top-level streams (eg, IFstream, OFstream) with additional information
  about the internal IOstream 'version' (eg, version: 2.0).

  Makes it more convenient to open files with a specified
  format/compression combination - no clutter of specifying the
  version

applications/test/decomposedBlockData/Test-decomposedBlockData.C

@@ -79,7 +79,6 @@ int main(int argc, char *argv[])
     (
         objPath,
         IOstreamOption::BINARY,
-        IOstreamOption::currentVersion,
         runTime.writeCompression()
     );
     if (!os.good())