core: sched: thread: optimize thread status field usage

see PR #716 for discussion
sys: update ps to reflect thread status variable changes
add oonf_api pkg
Changes to `thread_wakeup`

`thread_wakeup` did not check if target pid is invalid.

`thread_wakeup` used `dINT` and `eINT` directly.
It should use `disableIRQ` and `restoreIRQ` instead, because there might
be other (good) reasons why one might want to call `thread_wakeup` with
interrupts disabled.

`thread_wakeup` yielded even if the other thread had a lower priority
than the current thread.
Allow escaped characters in shell

Per #708.

This patch allows escaped characters in the shell, and makes the
apostrophe a quotation mark. The escape character is backslash.

The term "escape character" is used liberally in here: if a backslash is
encountered in the command line, the next character will be taken
verbatim. No escape sequences are understood, i.e. `"\n"` is just the
letter `n`, not a new line.
Don't use INCLUDES for building any native at all.

native modules will never need the dynamic INCLUDES, so we define our
own NATIVEINCLUDES. Due to the current make structure, the only way to
not use INCLUDES is to redefine the build rules.
native/posix: Don't include sys/types.h in sem

`sys/types.h` contains the native definition for `pthread_*_t`. This
causes clashes if you want to use `semaphore` and `pthread` in the same
application.
Add automatized test for sha256
ccnl: added documentation and proper event handling for dropped packets
pthread: mutex - return the right values
Merge pull request #804 from LudwigOrtmann/native_include_separation

native/make: Don't use INCLUDES for building any native at all.
Merge pull request #838 from mehlis/posix-mutex-fix

pthread: mutex - return the right values
Fix source address IPHC
posix: added sleep and usleep
test: added test case for posix sleep
Merge pull request #839 from mehlis/posix-sleep

posix: added sleep and usleep
Merge pull request #832 from mehlis/ccn-lite-follow-up-11

ccnl: added documentation and proper event handling for dropped packets
Merge pull request #806 from Kijewski/sem-pthread-native

native/posix: Don't include sys/types.h in semaphore.h
Merge pull request #794 from Kijewski/shell-args-escape

shell: Allow escaped characters in shell
Merge pull request #698 from Kijewski/thread_wakeup-dint

Changes to `thread_wakeup`