dcfldd: added advanced dd replacement
New packages: pam_mount and libHX

Add pam_mount package. Integration into NixOS is still missing.
Merge branch 'upstream' into pam_mount

Conflicts:
	pkgs/top-level/all-packages.nix
Fix description in pam_mount and libHX. Add tstrobel as maintainer.
nixos/libvirtd: refresh LXC emulator path on startup

This fixes the issue when the LXC emulator binary is garbage collected
and breaks libvirtd containers, because libvirtd XML file still refers
to GC'ed store path.

We already have a fix for QEMU, this commit extends the fix to cover LXC
too.
Add package: Enlightenment E19!

Wayland desktop shell is not enabled, yet.
Add configuration flag to chromium: hiDPISupport

By default, hiDPISupport is disabled.
agda-categories: add package
systemd: Support reload scripts
nixos/firewall: Don't allow traffic during reload
Merge pull request #4108 from wkennington/master.firewall

Firewall: Don't allow traffic during nixos-switch / reload
improve ruby support

* add the 2.1.x versions
* include teeny version in passthru
* by default, apply the same patches used by RVM
* clean up file names and attribute names
update camlistore to 0.8
nixos/firewall: Support extraStopCommands
nixos/nat: Leverage firewall module
Merge pull request #4111 from wkennington/master.nat

Allow nat to leverage the firewall unit if available
Merge pull request #4104 from ts468/chromium

Add configuration flag to chromium: hiDPISupport
Fixed URL in bashmount package.
fishshell builds on unix platforms
Merge pull request #4113 from bernerdschaefer/fish-darwin

fish-shell builds on unix platforms