linux: Add support for zram
rxvt-unicode: add 256-color resources patch
Enable encrypted backing devices in fileystem configurations
ssh: Support knownHost public keys as strings
sshd: Fix typing for options which take paths
hplip version bump 3.11.1 -> 3.14.4
hplip: add binary plugin
hplip: assume maintainership
hplip: add pillow and reportlab dependencies
sane: add mkSaneConfig
hplip: avoid name collision with sane config files
sane: use mkSaneConfig to set system environment
mupdf: build with -fpic
mupdf: build a shared library instead
openjpeg: provide .pc
zathura: mupdf plugin
hplip: don't use udev rules to change device owner
Add unicode3 option to rxvt_unicode

Needed to user fonts patched for powerline.
hipchat: Update to 2.2.1107
hipchat: Fix access to /usr/share/X11/xkb

HipChat (or rather its copy of Qt) expects to find keyboard data in
/usr/share/X11/xkb. So use a LD_PRELOAD library to intercept and
rewrite the Glibc calls that access those paths. We've been doing the
same thing with packages like Spotify, but now this functionality has
been abstracted into a reusable library, libredirect.so. It uses an
environment variable $NIX_REDIRECTS containing a colon-separated list
of path prefixes to be rewritten, e.g. "/foo=bar:/xyzzy=/fnord".