return a string that friendly print file size.

friendly-filesize.js

function friendlyFileSize(sizeInBytes) {
  if(sizeInBytes < 1024) {
    return `${sizeInBytes} Bytes`;
  } else if(sizeInBytes >= 1024 && sizeInBytes < 1048576) {
    return `${(sizeInBytes/1024).toFixed(2)} KB`;
  } else if(sizeInBytes >= 1048576) {
    return `${(sizeInBytes/1048576).toFixed(2)} MB`;
  }
}

// friendlyFileSize(123490421)
// "117.77 MB"