match db: add function to test against src_names and bloom filters
bus: reject bus creation if length of bloom filter is not a multiple of 8
test: fix message generating tools
match: add match function for kernel-generated messages
kmsg: store a short-hand to the type of kernel-generated notification types

A kernel-generated notification mesaage will only contain one single
payload type, so instead of searching for all possible data attachments,
we can as well just refer to a stored copy from match.c.

As fds are never passed with along with such a message, we can store the
two fields in a union.
fix kdbus_match_db_test_src_names
message: pass back required size when returning -ENOBUFS
rename our hack to the upcoming: task_cgroup_path_from_hierarchy()

http://git.kernel.org/cgit/linux/kernel/git/tj/cgroup.git/commit/?h=review-task_cgroup_path_from_hierarchy&id=8f2d788f3210ffed073bc57568befd9d757a15ef

Thanks a lot, Tejun!
kdbus.txt: fix typos
reword some error descriptions
use timespec_to_ns()
introduce KDBUS_MATCH_ITEM_FOREACH() to handle padded item sizes
bus: use KDBUS_IS_ALIGNED8
match: fix bloom filter check
use u8 instead of char in FOREACH macros
message: handle KDBUS_CMD_HELLO_ATTACH_CAPS
match.c: drop unused paramter
test: do not print caps bits to console
fix CAPS data length