EnglishTranslators: if only custom start timestamp is set, then we update
* the timestamp range button label in popover to show that
* logs are shown in the window starting from this timestamp
* until the ending timestamp of journal.
EnglishTranslators: if only custom end timestamp is set, then we update
* the timestamp range button label in popover to show that
* logs are shown in the window upto this timestamp
* with the starting timestamp being the current time.