crypto: get rid of compiler warnings
core: shadowing in priority_queue_print

The variable `node` shadows the parameter `node`. The access of
`node->first` would not compile, because there is no member `first` in
`priority_queue_t`.
Merge pull request #1563 from Kijewski/priority_queue_print-typo

core: shadowing in priority_queue_print
Merge pull request #1522 from OlegHahm/crypto_cleanup

crypto: get rid of compiler warnings
drivers/at86rf231: add transceiver/pid includes
Merge pull request #1567 from LudwigOrtmann/at86rf231_includes

drivers/at86rf231: add transceiver/pid includes
pyterm: Use only printf-style String Formatting

Needed for backwards compatibility to python 2.6. Refers to
https://github.com/RIOT-OS/RIOT/commit/46c38230ebb7cbc690ac77d1b649e29c536f1d0c#commitcomment-7363298
Merge pull request #1568 from authmillenon/pyterm-printf-style

pyterm: Use only printf-style String Formatting
core: introduce KERNEL_PID_FIRST and KERNEL_PID_LAST
native: remove redeclarations of sched_active_thread
all over the place: use sched_active_pid
core: remove PID check duplication
core: let valid PIDs start with 1
core: use sched_threads[0] to store sched_active_thread