adds the ability to modify the `documentation` property inside custom extractor handlers
make api method headers anchor links so a speicif method can be refered to through its unique id
Merge pull request #240 from kbsali/ids

Make it possible to refer to methods through a URI
Merge pull request #221 from kmfk/documentation-in-handler

Modify the `documentation` property inside annotation handlers
Merge branch 'master' of https://github.com/restyler/NelmioApiDocBundle