Custom message prefix and time unit

[Halogly]

1. Custom message prefix can be set
2. Configurable time units

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[Halogly]

Completed in #796