Using socket.io for websocket handling and make reforis configurable

Štěpán Henekrequested to merge
feature/ws-included into dev

Socket.io wrapper is used to handle websockets now, this means that websocket logic had to be redone.

Also it is necessary to set REFORIS_PREFIX env variable during the build process. To set the path of backend url. It was previously fixed to /reforis.

Merge request reports