fixed empty options, closes #19
updated doc
3.0.1
Merge branch 'master' of https://github.com/jsoverson/grunt-preprocess

* 'master' of https://github.com/jsoverson/grunt-preprocess:
  Allow the preprocess task to be renamed.
  Let target's context win over global context
  Added tests to prove context precedence error
  3.0.1
  updated readme
  fixed empty options issue, closes #19

Conflicts:
	README.md
	tasks/preprocess.js
updated readme
4.0.0