noc: remove ishmael & cleanup

ishmael has been moved into a module, a role class and a different box
(neon) for a while. Remove references to it from noc, and while at it,
remove a couple of other dangling references (graphite, Rails/Sinatra)
and some now-unused modules (LDAP, proxy, passenger).

Note that since the class is applied to just one box and for simplicity,
no ensure => absents are provided but these will be cleaned up manually.

Change-Id: I02dc96298b75c4aa7cf9e46cb006c21e11cdad60