shell: remove useless copying of input string
Add quadword math lib

GCC implicitly calls functions like __adddi3 to handle arithmetics on
long long.

Copied from http://ftp3.usa.openbsd.org/pub/OpenBSD/src/lib/libc/quad/
which is curtesy of the OpenBSD project (3 clause BSD license).
Add compile time checks to quad.h
Adapt quad lib to RIOT coding conventions
Do not zero out sched_threads needlessly

The function sched_init() zeroes out sched_threads needlessly. All
static variables can be assumed to be initialized with zero, anyways.
The C standard mandates it, and all at other places in the code it is
assumed.
Add a reboot() function to kernel.h definitions.
Implemented reboot() function for MSP430 MCUs
Add wireshark dissector for native packets
core: msg: don't wake up sender after receive if it's REPLY_BLOCKED

solves issue #100

If the sender is reply-blocked, waking it up after its message has been
delivered is wrong. It needs to stay reply-blocked until the reply has
been delivered.
core: msg: add some debug statements
core: msg: yield after queueing of a message if REPLY_BLOCKED

When setting the running task reply_blocked, it is implicitly removed
from the runqueue. But if queueing of a msg is actually successful, the
thread exits msg_send without yielding, continuing to run even if it's
not supposed to.

Nice example of why multiple function exit points lead to weird
errors...
Use `filter` instead of `findstring`

See #672
Introduce board blacklists and board whitelists
Function attributes are now defined elsewhere ("attributes.h")
Implemented reboot() function for ARM-based MCUs
Added while(1) to ensure GCC valids NORETURN; fixed indentation
Eliminate findstring in more places
Split `} else {` lines per #693
https://github.com/Kijewski/RIOT/commit/102dc453828012985f82915ad826be069f444e61#commitcomment-5378590
implement rudimentary native reboot