user and kernel crange.c are identical

If we don't -include compiler.h it's important to always include
the header with the attribute defines before they are used.
Otherwise the compiler will silently "fail" by defining variables
named the attribute define (e.g. __mpalign__).  Another option
is to remove the attribute defines, but I kind of like them.

Each core's gc thread free elements on the tofree list

Kernel is trickier because there are processes that don't call begin/end_epoch
Premature anyway, since it won't help until we have per-core process lists
But, we do garbage collect memory now

proc.c was using kfree, which places the two page stacks on the
single page free lists.

E.g.
  $ cat netif
  hw 52:54:00:12:34:56
  ip 10.0.2.15 nm 255.255.255.0 gw 10.0.2.2

Also disable annoying DHCP messages from kernel.