eventdctl: Minor style update

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
eventdctl: Add "version" command

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
autotools: Move Git versionning to m4

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
eventdctl.h: Fix typo

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
eventd/control: Style rework

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
eventdctl: Style rework

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
eventdctl: Rename variable for consistency

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
eventdctl: Send the argv directly

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
eventdctl: Split flags logic to a subcommand

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
eventdctl: Add "flags remove" command

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>