title: Save client generated data as file in JavaScript in chunks
body: <p>I'm developing a FileShare application with webRTC. I want to implement the client in JavaScript/HTML. The code should be run on the clients browser.
  I need to save them when downloaded via webRTC. The files can be quite big and I can't completely donwload them and save them in a array or blob before saving them to disk as a file.</p>
  
  <p>Is there any API that allows me to save the file in chunks as I recieve them?</p>
  
  <p>I have found so far <a href="https://github.com/dcneiner/Downloadify" rel="noreferrer">Downloadify</a>, <a href="https://github.com/eligrey/FileSaver.js" rel="noreferrer">FileSave.js</a> and <a href="http://caniuse.com/filesystem" rel="noreferrer">html5 FileWriterApi</a> so far.
  While the first two are not chunked and require me to first download the complete file to memory before saving, the FileWriterAPI is not available on most browsers. </p>