docs: function watchCompiler(compiler, options={}){
    let watching = false
    log('Watch Building')
    const startWatchTime = Date.now()
    const watchConfig = { // watch options:
      //aggregateTimeout: 300, // wait so long for more changes
      //poll: true // use polling instead of native watchers
      // pass a number to set the polling interval
    }
  
    options.onRebuild = options.onRebuild || function(){}
  
    return new Promise(function(res,rej){  
      //webpack watch functionality
      compiler.watch(watchConfig, function(err,stats){
        if(err)return rej(err)
  
        if(watching){
          log('Rebuilt '+getServerTime())
          options.onRebuild(stats)
        }else{
          watching = true
          log('Watching '+(Date.now()-startWatchTime)/1000+' seconds')
          res( this )
        }
      });
    })
  }