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
Merge pull request #1304 from thomaseichinger/fix_cc2420_rxfifo_of

boards: harmonise cc2420 isr
Merge pull request #1346 from Kijewski/hyphen-in-modulename

make: cortex m3: replace hyphen in module name
Merge pull request #1301 from cgundogan/fix_tcp_handshake_seq_ack_rfc_compliancy

destiny: wireshark revealed wrong seq/ack nr. in tcp handshake
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
Merge pull request #1354 from OlegHahm/nativenet_packetsize

nativenet: change max packet size to 127
Merge pull request #1335 from Kijewski/fix-all-warnings-for-native-and-qemu-i386

Fix all warnings for native and qemu-i386
cpu - sam3x8e: fixed vtimer, added timer_set_absolute
Merge pull request #1356 from haukepetersen/fix_sam3x_newlibnano

cpu - sam3x8e: added switch for newlib-nano specs
Merge pull request #1357 from haukepetersen/fix_cortexm3_threading

cpu: cortex-m3_common: cleanup thread_arch.c
Introducing a source routing header for RPL.
Merge pull request #1218 from fabianbrandt/srh_rpl

Introducing a source routing header for RPL.