ng_at86rf2xx: Clean up state transitions and netdev implementation

Fix some clang analyzer findings

num was never read, because native will exit before.

pkg/libfixmath: Protect svn checkout with a lock

scan-build: Add make goal for running Clang static code analyzer (ccc-analyzer)

openocd: don't reset cpu for target 'debug'

astyle: fix config

doxygen: documentation hierarchy fixes

Also remove doc.txt for sam3 (moved to cpu_conf.h)

cpu/kinetis_common: Cast device index enums to unsigned int before comparing for out of range values

sys/net/network_layer/ng_sixlowpan/iphc: Set IPv6 header length after decoding

cpu/kinetis_common: Cast device index enums to unsigned int before comparing for out of range values

Suppresses false warning in Clang:

    warning: comparison of constant 42 with expression of type 'xxx_t'
    is always false [-Wtautological-constant-out-of-range-compare]

See:
 - https://llvm.org/bugs/show_bug.cgi?id=16154
 - https://llvm.org/bugs/show_bug.cgi?id=22062

ng_ndp, fib: Two small code style fixes

Explain how to connect RIOT to Linux

doxygen: add make targets to build man and latex

libcoap: switched to new "official" Github repo

HTML will be build per default.

drivers/hih6310: Initial commit of HIH6310 driver

Uses BPSK-40 for all frequencies.