Add another synchronization interval

[ddeimeke]

Hi!

In the App there are synchronization intervals like the following:

• 15 Minutes
• 30 Minutes
• 1 Hour
• 12 Hours
• 24 Hours

Would it be possible to add one between 1 hour and 12 hours? Either 4 hours or 6 hours (or even configurable) would be perfect.

Thanks!

Dirk