index.js
function createHeader (type, size) {
  var header = new Buffer(8);
  header.writeUInt8(type, 0);
  header.writeUInt32BE(size, 4);
  return header;
}
function createHeader (type, size) {
  var header = new Buffer(8);
  header.writeUInt8(type, 0);
  header.writeUInt32BE(size, 4);
  return header;
}
function createHeader ( type , size ) { var header = new Buffer ( 8 ) ; header . writeUInt8 ( type , 0 ) ; header . writeUInt32BE ( size , 4 ) ; return header ; }
create a docker frame header
@param {number} ioConnectionType - 2=stderr, 1=stdout, 0=stdin
@param {string|buffer} payloadData
@returns {buffer} header - frame header (type, length) as buffer
create a docker frame header