pull module blacklist from Ubuntu and use it by default

People often have serious problems due to bogus modules like *fb.
lightdm: Update to 1.8.6
lightdm-gtk-greeter: Update to 1.6.1
kmod-blacklist-ubuntu: fetch from tar.gz, not bazaar

Now the source is just a miniature archive.
kmod-blacklist-ubuntu: fix references to binaries
siege: Update to 3.0.6
siege: expression cleanup
nixos/nscd: add option to change nscd config

[Bjørn Forsman <bjorn.forsman@gmail.com>:
 - use types.lines instead of types.string. The former joins strings
   with "\n" and the latter with "" (and is deprecated).
]
Merge #1618: use ubuntu module blacklists by default
Merge #1645 and #1646: lightdm and -gtk-greeter update
switch-to-configuration.pl: Handle successful auto-restarts

switch-to-configuration.pl is currently hard-coded to assume that if a
unit is in the "auto-restart" state that something has gone wrong, but
this is not strictly true. For example, I run offlineimap as a oneshot
service restarting itself every minute (on success). NixOS currently
thinks that offlineimap has failed to start as it enters the
auto-restart state, because it doesn't consider why the unit failed.

This commit changes switch-to-configuration.pl to inspect the full
status of a unit in auto-restart state, and now only considers it failed
if the ExecMainStatus is non-zero.
Update/fix farstream: Gajim now at least builds
Fix wvdial build by inserting missing unistd.h includes
Create an attribute for latest ocaml packages even when this is not the default version
Update Aria download manager
Use dynamical libbfd because static one is searched in strange places
Update GCL source to latest release
libcdio-0.82 for abcde

libcdio-0.9x lacks cd-paranoia needed by abcde. Bring back 0.82 for
abcde until we sort out where cd-paranoia went to.
texlive: Fix download file names to be current.
fix libcdio filename