destiny: fixed condition for error handling
send_tcp returns either the length of the sent data,
or -1, if an error was detected.

The current implementation checks for != 1.
This results in executing the error case, although
there was semantically no error returned from send_tcp.
core/include/arch/irq_arch.h: fix typo and trailing whitespaces
Merge pull request #1308 from N8Fear/fix-typo-and-whitespaces

core/include/arch/irq_arch.h: fix typo and trailing whitespaces
cpu: renamed cortexm_common->cortex-m3_common and cleanup
pnet: silence unused argument warnings
Merge pull request #1295 from haukepetersen/mv_cpu_cortexm-common

cpu: renamed cortexm_common->cortex-m3_common and cleanup
Merge pull request #1312 from mehlis/pnet-unused-param

pnet: silence unused argument warnings
cpu:cortex_common: add core_panic function
Merge pull request #1313 from thomaseichinger/cortexm_crash

cpu:cortex_common: add core_panic function
Merge pull request #1280 from cgundogan/fix_send_tcp_error_check

destiny: fixed condition for error handling of send_tcp in destiny_socket_send
make: remove local definitions of (ELF|HEX)FILE

We have sane defaults for `ELFFILE` and `HEXFILE` in the root
`Makefile.include`. The local definition for `ELFFILE` of mbed_lpc1768's
`Makefile.include` was wrong, which caused e.g. `make buildsize` to
fail.
Merge pull request #1303 from Kijewski/mbed_lpc1768-fix-result-paths

make: remove local definitions for ELFFILE and HEXFILE (was: "mbed_lpc1768: fix ELF and HEX paths")
Initial commit of Arduino Mega2560
strip functions in atmega2560/periph and atmega_common/thread_arch.c down to prototypes

Add custom errno.h since avr-libc doesn't include one
rename board_init to main, main to o_main (inside hello-world/main.c). Fix
Makefile.include:

UART works within RIOT codebase, :)
Develop: fix invocation of avrdude
arduino-mega2560: cleanup, add interrupt driven uart communication
SQUASHME: return examples/hello-world/main.c to original state
Arduino Mega2560: Make reset_handler entry point and move ISR to startup.c

    Create .init7 and .init8 sections to circumvent call to main
    Move ISR for UART0_RX to startup.c
    Some cleanup
Arduino Mega 2560: remove instrumentation from board_init()