lib/sysfs: allow to write to sysfs attributes

Signed-off-by: Karel Zak <kzak@redhat.com>
lib/ismounted: make it more compatible with lsblk output

Signed-off-by: Karel Zak <kzak@redhat.com>
zrmactl: add new command to control /dev/zramN devices

Co-Author: Timofey Titovets <nefelim4ag@gmail.com>
Signed-off-by: Karel Zak <kzak@redhat.com>
cal: add const function attributes

Reference: http://lwn.net/Articles/285332/
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
cal: prefer defined constant rather than magic values

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
tests: kill output message change

Commit 09af3db48e01e5744f15fd8a2395e0fed36526ea changed how a missing
process is reported, which caused kill test to fail when the test suite
is ran as root.

Reference: https://travis-ci.org/karelzak/util-linux/jobs/31312170
Signed-off-by: Sami Kerola <kerolasa@iki.fi>