.travis.yml: Enable the PACCT module

Signed-off-by: Gergely Nagy <algernon@balabit.hu>
lib/persist-state.c: Do include misc.h aswell

We're using g_fd_set_cloexec() from misc.c, so include the appropriate
header aswell, or we get a compile-time warning.

Reported-by: Michael Sterrett <mr_bones_@gentoo.org>
Signed-off-by: Gergely Nagy <algernon@balabit.hu>