Development branch towards 2016.10 release

Main purpose of this tag is to fix the output of git describe.

RELEASE 2016.07

Merge pull request RIOT-OS#5703 from wentaoshang/fix-sha256

hashes: support unaligned memory access in be32enc_vect

Merge pull request RIOT-OS#5676 from jasonatran/cc2538_debug

cpu/cc2538: fix debug statements

RELEASE 2016.04

RIOT-2016.04 - Release Notes
============================
RIOT is a real-time multi-threading operating system that supports a range of
devices that are typically found in the Internet of Things: 8-bit
microcontrollers, 16-bit microcontrollers and light-weight 32-bit processors.

RIOT is based on the following design principles: energy-efficiency, real-time
capabilities, small memory footprint, modularity, and uniform API access,
independent of the underlying hardware (this API offers partial POSIX
compliance).

RIOT is developed by an international open source community which is
independent of specific vendors (e.g. similarly to the Linux community)
and is licensed with a non-viral copyleft license (LGPLv2.1), which allows
indirect business models around the free open-source software platform
provided by RIOT.

About this release:
===================
This release adds support for two additional network stacks: lwIP and emb6.
A bunch of additional protocols are now available, P2P-RPL in the GNRC
network stack, Ethernet-over-Serial (ethos). Murdock, the new, blazing fast
RIOT CI is now available to significantly speed up code merging procedures.

This release also adds support for a number of new boards and sensors and a new
tool for automated border router setup is now provided which greatly simplifies
that setup for newbies as well as for old-timers. Last but not least: this
release includes a number of bug fixes, mostly about stabilizing and enhancing
the networking capabilities of RIOT.

About 470 pull requests with about 1196 commits have been merged since the last
release and 127 additional issues have been solved. 55 people contributed code
in 124 days. 1521 files have been touched with ~91700 insertions and ~42200
deletions.

Notations used below:
=====================
+ means new feature/item
* means modified feature/item
- means removed feature/item

New features and changes
========================
General
----------
+ added Makefile support for creating a "binary distribution", making it easier to create closed source applications while still complying to LGPL

Testing

Merge pull request RIOT-OS#5386 from cgundogan/pr/backport/disable_nhc

make: disable NHC (backport of RIOT-OS#5385)

Merge pull request RIOT-OS#5379 from cgundogan/pr/backport/rm_rf_safe

make: bail out if there are spaces in the path (backport of RIOT-OS#5221)

Development branch towards 2016.07 release

Main purpose of this tag is to fix the output of git describe.

Merge pull request RIOT-OS#5240 from basilfx/feature/si70xx_improvements

drivers: si70xx: result bugfixes

This is release 2015.12 of RIOT.