libc: removing newlib, adding BSD libc
posixcompat: moving gettimeofday to libc
harness: adding a simple math test
lwip, lwip2: moving includes to /include, compiling with BSD headers

Signed-off-by: Adam Turowski <adam.turowski@inf.ethz.ch>

Squashed 'lib/newlib/' content from commit a4e9d13

git-subtree-dir: lib/newlib
git-subtree-split: a4e9d133a8a6cb9a4a5302005c974cbc6b82de42

Signed-off-by: Simon Gerber <simon.gerber@inf.ethz.ch>