fix(docs): Fix warning: 'end is deprecated, use done instead.'

- There's a warning due to ./node_modules/[email protected] --> node_modules/[email protected]
- This may also be due to package.json not being restrictive enough on the q-fs version.
- In any case, q-fs is being retired for q-io/fs, so this fix is probably necssary eventually.

Author: kmayer

docs/src/gen-docs.js

@@ -36,7 +36,7 @@ writer.makeDir('build/docs/', true).then(function() {
   });
 }).then(function printStats() {
   console.log('DONE. Generated ' + docs.length + ' pages in ' + (now()-start) + 'ms.' );
-}).end();
+}).done();
 
 
 function writeTheRest(writesFuture) {