Remove kernel features (for embedded systems)

[Felix von Leitner <felix-kernel@fefe.de>]

I propose to add the following kernel features to the removables:

  * /dev/kmem and /proc/kcore
  * core dumping
  * ptrace

And if it is at all possible, I would like to be able to remove parts of
the IP stack, e.g. routing.  In particular, I would like to be able to
remove policy routing, if it is at all worth it from the code size point
of view.

Removing ptrace and kmem is mostly for security reasons, but being able
to remove them makes sense in embedded environments as well.

Felix