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.
destiny: using a bit field for tcp_header->data_offset is more convenient
In the current implementation the data offset is coded into an uint8_t.
Of this uint8_t only 3 bits apply for the data offset.
The remaining bits represent reserved flags for future use.
However, a proper bit masking is forgotten in order
to obtain the data offset part of this uint8_t.

Therefore, defining this uint8_t as a bit field allows a more convenient
method of access.
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")
Merge pull request #1302 from cgundogan/fix_tcp_header_data_offset

destiny: using a bit field for tcp_header->data_offset is more convenient
dist/tools: add license checker

Creates file structure that maps files to licenses by grepping for
license patterns (patterns for licenses found in RIOT included).
Sets exit code to 1 if an unknown license header is detected.
Merge pull request #1181 from LudwigOrtmann/licenses

license checker
lpc2387: change comment style for license checker
cortex: change comment style for license checker
lpc2k: unify Paul Stoffregen license headers