doc: fix language

"the sender and nobody else" == "only the sender", which is definitely not
what was meant here. Fix this.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
kdbus.txt: minor fixes
kdbus-monitor: cleanup and fix
message: disallow passing of both kdbus handles and unix domain sockets

Both can be used to pass a file descriptor that itself can pass another
file descriptor. For now, disallow them both.
kdbus.txt: spelling
queue: fix integer signedness confusion
test: fix and reenable message prio test
match, names: fix two coverity issues

Plug a resource leak, and check the return value of kdbus_pool_slice_copy().
test: cleanups
pool: release lock in exit path
test/test-names.c
style fixes
test: some tests to enforce routing messages by connections ID

Add kdbus_fork_test_by_id() to test connections by id under different
uids. Currently we succeed at this test.

Update:
1) kdbus_msg_recv() to get the offset of the slice, so we can
release it later.

2) kdbus_msg_recv_poll() to pass the offset argument to
kdbus_msg_recv().

We do this to follow best practice and to be able to free the returned
kdbus_msg and the slice pointed by that offset.

Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
test: Use 'CapBnd' string for capability bounding set

Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
pool: cleanups