B: fix reaped link in docs
B: fix reaped link in docs

it was pointing to a dead link. now, it'll point to the new section
created in concourse/docs#407

Signed-off-by: Aidan Oldershaw <30ef7a6e0d016bc846f26d89dacbd23aceded206@pivotal.io>

concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse,concourse/concourse