vtimer: fix callback usage

There is no need to test the "handler" set in the vtimer struct, and
have some code executed then. We just can make the code to execute the
handler. To lengthy `if else if`, just a call.
lpc1768: cleanup Makefile

`cpu/lpc1768/Makefile` contains many lines that don't belong into this
file, but the maybe `Makefile.include`. Either way, this Makefile is
never called with these goals.
destiny: wireshark revealed wrong seq/ack nr. in tcp handshake
Capturing the tcp handshake with wireshark revealed that the
sequence and ack nrs. are not rfc compliant.
I did the changes based on
http://tools.ietf.org/html/rfc793#page-52 to http://tools.ietf.org/html/rfc793#page-72
Fix all warnings for native and qemu-i386

Missing returns, unused variables (only used for debugging), empty
translation units, missing function prototypes, and GNU extensions.
make / cortex m: replace hyphen in module name

When you compile for UDOO, you are greeted by a multitude of this
warnings:
```
<command-line>:0:14: warning: ISO C99 requires whitespace after the macro name [enabled by default]
```

The reason for that is the argument `-DMODULE_CORTEX-M3_COMMON`.

This PR fixes this problem by replacing hyphens with underscores for the
`-D…` argument.
native: implement hwtimer removal
boards: harmonise cc2420 isr

TelosB, wsn430-v14, Z1
nativenet: change max packet size to 127

Real IEEE 802.15.4 transceivers have a payload of 127. Hence, for
testing - particular 6lowpan - it would make sense to have the same
limitation in nativenet. Especially to test fragmentation this is
helpful.
cpu cortex-m3_common: cleanup thread_arch.c
cpu - sam3x8e: added switch for newlib-nano specs
cpu - sam3x8e: fixed vtimer, added timer_set_absolute
ccnl: fixed commenting style
ccnl: eliminated empty translation unit warning
Introducing a source routing header for RPL.
boards: removed -lto flag and cleanup for udoo&arduino due
Split RPL into core and mode related functions.
drivers - gpio: expanded gpio driver interface

- added functions for en|disabling a pins interrupt
driver - gpio: small adjustments
applications: set stack size correctly

The correct stack size for all examples and test applications correctly.
KERNEL_CONF_STACKSIZE_MAIN is the correct stack size for any thread
using printf.

Also adapted black lists accordingly.
sys/ps: s/float/int for runtime

The high precision isn't needed, use per mille instead.
Circumvents printf problems on some platforms.

Also: prevent division by zero.