Prefix forms names with "afe_" string
Update documentation
Missing prefixes
Fix stylesheet/javascript functions render
Merge pull request #81 from avocode/feature-addingPrefix

[BC Break] Feature adding prefix

BC Break : 
 - all forms have been prefixed with `afe_` string
 - Twig functions `form_javascript()`  and `form_stylesheet` have been prefixed with `afe_`
 - Javascript and Stylesheet form blocks have the following format: 
    * `formname_afe_javascript`
    * `formname_afe_javascript_prototype`
    * `formname_afe_stylesheet`