fix debian lintian errors and warnings

[dmatetelki]

E: batterystatusled: debian-changelog-file-missing
E: batterystatusled: no-copyright-file
E: batterystatusled: wrong-file-owner-uid-or-gid lib/ 1000/1000
E: batterystatusled: wrong-file-owner-uid-or-gid lib/systemd/ 1000/1000
E: batterystatusled: wrong-file-owner-uid-or-gid lib/systemd/system/ 1000/1000
E: batterystatusled: wrong-file-owner-uid-or-gid ... use --no-tag-display-limit to see all (or pipe to a file/program)
E: batterystatusled: bad-owner-for-doc-file usr/share/doc/README.md dmatetelki/dmatetelki != root/root
E: batterystatusled: file-directly-in-usr-share-doc usr/share/doc/README.md

W: batterystatusled: description-starts-with-leading-spaces
W: batterystatusled: unknown-section base
W: batterystatusled: non-standard-dir-perm lib/ 0775 != 0755
W: batterystatusled: non-standard-file-perm usr/share/doc/README.md 0664 != 0644
W: batterystatusled: binary-without-manpage usr/bin/battery_status_led.sh
W: batterystatusled: non-standard-dir-perm lib/systemd/ 0775 != 0755
W: batterystatusled: non-standard-dir-perm lib/systemd/system/ 0775 != 0755
W: batterystatusled: non-standard-file-perm lib/systemd/system/battery_status_led.service 0664 != 0644
W: batterystatusled: non-standard-dir-perm ... use --no-tag-display-limit to see all (or pipe to a file/program)
W: batterystatusled: script-with-language-extension usr/bin/battery_status_led.sh
W: batterystatusled: non-standard-executable-perm usr/bin/battery_status_led.sh 0775 != 0755

[dmatetelki]

run it in fakeroot: https://github.com/dmatetelki/battery_status_led/blob/master/debian/package-deb.sh#L47