Update readme.md

Example gulpfile uses `rename`, but `rename` is not defined in the list of required modules.
fix nested batch folders
Merge pull request #2 from bradcerasani/patch-1

Update readme.md
Merge pull request #3 from bumbu/master

Allow to have nested folders for batch
Added 'html' as an "allowed extension"

It's unclear to me why you would want to limit files extensions, and this addition has stopped [my project](https://github.com/flovan/headstart) from working, without an easy fix (other than this PR) in sight.
I hope you won't mind accepting this small change.
Side note: please publish this module to NPM so future problems can be avoided. The only way of having the latest version is by linking to the Github version, which is subject to changes at any given time.
Merge pull request #5 from flovan/patch-1

Added 'html' as an "allowed extension"
Merge remote-tracking branch 'upstream/master'

fixed conflicts

Conflicts:
	index.js
fixed a issue where the data object was being referenced instead of
copied