lib/core.js
function mergeOptions(parsedOptions) {
    return Object.keys(autoflowOptions).reduce(function (accum, k) {
      if (!accum[k]) accum[k] = autoflowOptions[k];
      return accum;
    }, parsedOptions);
  }
function mergeOptions(parsedOptions) {
    return Object.keys(autoflowOptions).reduce(function (accum, k) {
      if (!accum[k]) accum[k] = autoflowOptions[k];
      return accum;
    }, parsedOptions);
  }
function mergeOptions ( parsedOptions ) { return Object . keys ( autoflowOptions ) . reduce ( function ( accum , k ) { if ( ! accum [ k ] ) accum [ k ] = autoflowOptions [ k ] ; return accum ; } , parsedOptions ) ; }
the top emitter 
merge global autoflow options with parsed options
the top emitter merge global autoflow options with parsed options