Introduce child process types.

'do random syscalls' is just one type. (And right now, the only one).

More to follow.
Create a directory for all the child processes
add a second child type. (read all files)

This is disabled for now, because it's pretty dull, and there is
some more groundwork to do before we can have multiple child types running.
net/alg.c: Include compat.h.

This patch fixes this build error with glibc before 2.13.

  CC	net/alg.o
net/alg.c: In function ‘alg_gen_sockaddr’:
net/alg.c:21: error: ‘PF_ALG’ undeclared (first use in this function)
net/alg.c:21: error: (Each undeclared identifier is reported only once
net/alg.c:21: error: for each function it appears in.)

Signed-off-by: Vinson Lee <vlee@twitter.com>
net/caif.c: Include compat.h.

This patch fixes this build error with glibc before 2.13.

  CC    net/caif.o
net/caif.c: In function ‘caif_gen_sockaddr’:
net/caif.c:22: error: ‘PF_CAIF’ undeclared (first use in this function)
net/caif.c:22: error: (Each undeclared identifier is reported only once
net/caif.c:22: error: for each function it appears in.)
make: *** [net/caif.o] Error 1

Signed-off-by: Vinson Lee <vlee@twitter.com>