Revert unintentional regression of samtools

Revert commit 4bf16eb80cd9e09a05a3c69b07c6a1848c1e7e2e
armadillo 3.920.2
armadillo 3.920.2

Closes #418
octave: patch unordered_map bug in configure

Patch to configure, due to a bug in configure.ac, where the ability to
use std::unordered_map as opposed to std::tr1::unordered map was
incorrectly tested, breaking the build on OS X 10.9.

Closes #414
octave: Incorporate upstream patch for std::unordered_map detection.

Follow-up #414.
ROOT: Update to 5.34.11 for 10.9 support

This commit bumps ROOT to version 5.34.11.

It also adds a HEAD URL/branch for additional patches to the current
ROOT release.  The HEAD branch points to the *official* ROOT GitHub
mirror instead of the CERN git server simply because the CERN git server
is primarily for internal use.  While HEAD support is not strictly
necessary for 10.9, adding HEAD will allow users access to more 10.9
patches (since support is still incomplete) before the next ROOT
release.