Ability to specify times/durations in config as user-friendly strings

[bennybp]

Description

For various fields, the config requires you to specify the time something takes in seconds. This is not ideal for long durations (hours to days). This PR adds the ability to specify these in three ways:

• As integer or string seconds (same as before): 90, "90"
• As dhms with a colon separator: 1:04:08:10 (1 day, 4 hours, 8 minutes, 10 seconds)
• As dhms with a suffix for each part: 1d4h7s (1 day, 4 hours, 7 seconds)

The conversion code is tolerant of leading zeros and weird quantities (ie, 1d77h99m99s)

Status

• Code base linted
• Ready to go