FIX: Question draft view crashes

Single question view was trying to display list of answers along single
draft. This list is not gathered by controller in draft route (and
should not be). Fixed by enclosing entire answers section inside `unless
draft`.
Model Controller respects res.locals.redirect

In following routes: new, save, apply, remove, add reference, remove
reference, after doing it's job Controller sends HTTP redirect. Now
location can be controlled by setting res.locals.redirect to desired
URL. It set in post callback, for example. This will be demonstrated in
answers' controller's apply route coming in next commit.

Also fixed remove route, which wasn't calling post callback at all.
Answers' drafts cab be applied

Added draft and apply routes to answer controller. Apply route uses new
res.locals.redirect functionality introduced in previous commit
(958b37d0001f130ce81e28bdace534f989f3db79).

Also introduced appropriate changes in single answer view.