replacing umlaute and fixing address in headers Haldeneggsteig -> Universitaetsstrasse

Signed-off-by: Reto Achermann <reto.achermann@inf.ethz.ch>

Rename struct slab_alloc to struct slab_allocator.

We have a function with the following signature:

void *slab_alloc(struct slab_alloc *);

which produces the following error message with g++:

error: ‘void* slab_alloc(slab_alloc*)’ hides constructor for ‘struct
slab_alloc’ [-Werror=shadow]

The two easy ways out are 1) renaming the function or 2) renaming the struct.
For clarity (and consistency with malloc and co) I've chosen to rename the
struct to "struct slab_allocator".

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

slab: do not use extra space for block header

headers: wrap declarations in extern "C".

Note: this change is not exhaustive and only touches some headers in //include

Initial version of public stable barrelfish repository.