gnu: python-sip, python-pyqt: Fix computation of python library path.

* gnu/packages/qt.scm (python-sip, python2-sip, python-pyqt, python2-pyqt,
    python-pyqt-4, python2-pyqt-4)[arguments]: Fix computation of python
    library path for multi-digit python versions.

tests: containers: Skip if setgroups file does not exist.

Fixes bug #21226.

Linux 3.19 introduced a fix for a security vulnerability in user namespaces.
This fix introduced a new proc file called 'setgroups' and was backported to
many older kernels.  However, some users run a kernel that is new enough to
support user namespaces yet old enough to not include the patch, so we must
skip the tests.

* tests/containers.scm: Skip all tests if /proc/self/setgroups does not exist.

gnu: Add epiphany.

* gnu/packages/gnome.scm (epiphany): New variable.

gnu: python-pyqt-4: Update to 4.11.4.

* gnu/packages/qt.scm (python-pyqt-4, python2-pyqt-4): Update to 4.11.4.

gnu: python-pyqt: Update to 5.5.

* gnu/packages/qt.scm (python-pyqt, python2-pyqt): Update to 5.5.

gnu: python-sip: Update to 4.16.9.

* gnu/packages/qt.scm (python-sip, python2-sip): Update to 4.16.9.

import: elpa: Fix typo.

Reported by Eric Dvorsak <eric@dvorsak.fr> on #guix.

* guix/scripts/import/elpa.scm (%default-options): Remove redundant
  quote which led to an error if --archive option was not specified.

gnu: Bump python-six to 1.9.0.

* gnu/packages/python.scm (python-six): Bump to 1.9.0.

gnu: Add redis.

* gnu/packages/databases.scm (redis): New variable.

gnu: Add simple-scan.

* gnu/packages/gnome.scm (simple-scan): New variable.

gnu: Add gusb.

* gnu/packages/gnome.scm (gusb): New variable.

gnu: Add gtk-doc.

* gnu/packages/gtk.scm (gtk-doc): New variable.

Modified-By: Mark H Weaver <mhw@netris.org>

gnu: sane-backends: Support USB scanners.

* gnu/packages/scanner.scm (sane-backends): Build with libusb-compat as an
  input and install a udev rule to give users access to scanners.

Modified-By: Mark H Weaver <mhw@netris.org>

gnu: Add libusb-compat.

* gnu/packages/libusb.scm (libusb-compat): New variable.

Modified-By: Mark H Weaver <mhw@netris.org>

gnu: Move ghostscript-with-x into (gnu packages ghostscript).

* gnu/packages/gv.scm (ghostscript/x): Move ...
* gnu/packages/ghostscript.scm (ghostscript/x): ... to here.

build: container: Add #:host-uids argument to call-with-container.

It's not always possible to map 65536 uids when creating a container as the
root user within another user namespace.  This is true when building Guix
within the build daemon's container.  By using a uid range of 1 by default,
even as the root user, the tests now pass.

* gnu/build/linux-container.scm (initialize-user-namespace, run-container):
  Add 'host-uids' argument.
  (call-with-container): Add #:host-uids keyword argument.
* tests/containers.scm ("container-excursion"): Update 'run-container' call.

build: file-systems: Allow for bind mounting regular files.

* gnu/build/file-systems.scm (regular-file?): New procedure.
  (mount-file-system): Create a regular file instead of a directory when bind
  mounting a regular file.

gnu: aalib: Pass --build to configure.

* gnu/packages/video.scm (aalib)[arguments]: In configure phase, accept
  'build' keyword argument and pass it to 'configure'.

gnu: icecat: Add fix for CVE-2015-4495.

* gnu/packages/patches/icecat-CVE-2015-4495.patch: New file.
* gnu-system.am (dist_patch_DATA): Add it.
* gnu/packages/gnuzilla.scm (icecat)[source]: Add patch.  Move the 'patches'
  field above the snippet.

gnu: python-2: Update to 2.7.10.

* gnu/packages/patches/python2-sqlite-3.8.4-test-fix.patch,
  gnu/packages/patches/python-libffi-mips-n32-fix.patch: Remove files.
* gnu-system.am (dist_patch_DATA): Remove them.
* gnu/packages/python.scm (python-2): Update to 2.7.10.  Remove patches.
  Update comment showing test failures.