ISO time hyphen/slash inconsistency

[walramb]

The setting for absolute time stamps claims to use the YYYY-MM-DD ISO date format, but it's apparently actually using the slash-separated, slightly incompatible YYYY/MM/DD format.
I checked the code to make sure it's not related to my locale and it looks like the ConvertTimestampToPrettyTime function is hardcoded to use slashes.

This could lead to some minor mishaps if a user tries to copy-paste a stamp into a place that wants real ISO.

[bbappserver]

ISO 8601 for reference

This is not so much an inconsistency as that 8601 never uses slashes and only uses dashes.

It is likely that the slashing is either as a result of using the system locale or a hardcoded format string.

[hydrusnetwork]

Thank you, this is fixed for tomorrow's 407.