boost: Add optional Boost.MPI support

Boost.MPI is a C++ interface library to the
message passing interface (MPI) standard.
android-ndk: r9d -> r10c
Removed duplicate
ghostscript: drop GNU fork and update
qpdf: add package
ijs: add package
cups: update package
cups-filters: add package
epdfview: fix building with cups 2.0
pycups: update package
foomatic-filters: fix building with cups-2
gtk3 stack: go back to gnome-3.12 branches for now
Allow starting a shell on stage 1 failure

When people copy the ISO to USB it can happen that the root device isn't known. Having a shell greatly improves that situation.
libfm: update frm 1.2.2.1 to 1.2.3
pcmanfm: update from 1.2.2 to 1.2.3
sxiv: update revision

Mainly to kick off Hydra again: it thinks the build is broken because we
used a SSH URL for git before.
mpd: update to 0.19.3
goffice_0_8: Fix build
kyotocabinet: Add derivation
tokyocabinet: 1.4.46 -> 1.4.48