[#86] Added documentation of controller_class config
[#86] Added documentation of controller_class config

nocvp/zf-rest,weierophinney/zf-api-problem,rstgroup/zf-api-problem,nocvp/zf-api-problem,rstgroup/zf-api-problem,weierophinney/zf-api-problem,Cube-Solutions/zf-hal,Cube-Solutions/zf-hal,weierophinney/zf-api-problem,Wilt/zf-hal,Wilt/zf-rest,rstgroup/zf-api-problem,nobesnickr/zf-hal,vixriihi/zf-jsonld,Cube-Solutions/zf-hal