Add ability to edit CfP

[ricco386]

Any one can submit CfP: http://127.0.0.1:8000/<slug>/cfp/ it creates speaker and talk. Create new view that will allow edit submitted data.

New view should be available via url: http://127.0.0.1:8000/<slug>/cfp/<uuid>. We should search talk uuid and return form so speaker can edit already submitted data. Edit should be available only if status is CFP or DRAFT otherwise show 404 page.

[ZoltanOnody]

I'll do it.