usemin - use the same technique of file replacement for css/img than js'
usemin - use the same technique of file replacement for css/img than js'

* file expand of every file within output postfixed by assets reference
* relative path handling
* replacement of css / js if found, otherwise skip it probably
  concatenated into another file
* replacement of img if found, otherwise leave off the actual content
* absolute and external uris ignored

mklabs/node-build-script,mklabs/node-build-script