URL encode links when a redirector is set.

Fixes #328 - URL encode links when a redirector is set

  * WARNING - template edit - new variable available : "real_url"
  Contains the final real url (redirected or any other change on original URL)

  * Don't redirect shaares link in RSS/Atom.
  * Affects links shaared in description.
  * Move text2clickable and keepMultipleSpaces to Utils.php + unit test

UPDATE:

* keepMultipleSpaces renamed to space2nbsp
* space2nbsp improved to handle single space at line beginning
* links in text description aren't 'nofollow' anymore