move IO types to modules comment block, https://github.com/phetsims/phet-io/issues/1396
move IO types to modules comment block, https://github.com/phetsims/phet-io/issues/1396

Signed-off-by: Chris Malley <74b2712074b149d140079dbd7e875955d192e617@pixelzoom.com>

phetsims/phetcommon,phetsims/phetcommon,phetsims/phetcommon