Close race on req->wrk clearing introduced in 6f2e1bcd

The disembarking thread would clear the req->wrk pointer in
CNT_Request. The req could have already been rescheduled on another
worker at this point, causing the req->wrk to be cleared while
processing. Change back to not clearing the pointer for
REQ_FSM_DISEMBARK (it's already been done under mutex in HSH_Lookup
anyways).

Fixes: #1488
Sync with reality

Update board members, URLs, spelling and fmt(1).
Fix up req.esi to only be available in client context.

Fixes: #1489
Spotted by: xcir
RPM: find-provides should not call find-requires.

Also remove the libvarnishapi "workaround" we put in place
earlier.

Found by: Ingvar Hagelund

Fixes: #1484