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
x86: shutdown on LPM_POWERDOWN
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.
drivers: added set_absolute to timer interface
Merge pull request #1289 from haukepetersen/fix_drivers_periph_timer

drivers: added set_absolute to timer interface
make: OSX: don't fail for empty .a archives

Fixes issue #1333.
tests/Travis: run unittests on x86, too
Merge pull request #1252 from Kijewski/travis-x86

tests/Travis: run unittests on qemu-i386, too
Merge pull request #1334 from Kijewski/issue-1333

make: OSX: don't fail for empty .a archives
Changed RIOT/Makefile.include, Makefile.base, Makefile.cflags, and native/Makefile.include to compile C and C++ files.
added riot_and_cpp example
added sudo apt-get install g++-multilib to travis.yml
Merge pull request #981 from vanhieubk/nhat_mixCompiler

Another way to mix c and cpp in user app with RIOT [native]
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.
bugfix: msp430 can write now more then one byte to flash
Merge pull request #1348 from SGSSGene/bugfix_writetorom

msp430: fix writing more than one byte to flash
pyterm: made python compatible with python2 and python3

In python 3 there is no implicit converion of bytes to str or character.
Merge pull request #1349 from cgundogan/fix_pyterm_python_version

pyterm: made python compatible with python2 and python3