Adds URL correct formatting

Adds correct formatting of URLS in example, and note about usage of trailing slash.
fix syntax in singular example also (README)
update to wording on usage
clarify trailing slash usage
Merge branch 'master' of git://github.com/jglovier/jekyll-redirect-from into jglovier-master

* 'master' of git://github.com/jglovier/jekyll-redirect-from:
  clarify trailing slash usage
  update to wording on usage
  fix syntax in singular example also (README)
  Adds URL correct formatting

Conflicts:
	README.md