Memset test for investigating aliasing problems
Remove work around for issue #452
memset test: add automated validation
Release notes for Genode 13.02
USB: Rewrote back-end allocators

Allocate back-end memory dynamically.
FOC: Do not touch memory in prepare_map_operation

At this point and in the current implementation, the memory has been mapped
and cleared already. Touching the memory may only pollute the cache of DMA
memory.

Fixes issue #452