Timestamp from every question is identical

[a-kempka]

Using quizaccess_offlinemode sets the "time saved" in each question to the time of the completion of the whole quiz. This is problematic, as a reviewer cannot reconstruct the course of events in the quiz, e.g.

• if a student possibly cheated and pasted all the answers shortly before completion or if they were filled out in a plausible pattern
• if multiple students typed their answers simultaneously as there is no reliable timestamp of answers
• if answers were changed
• if the questions were answered in a plausible order (or in the same as another student)
  The problem persists not only while disconnected, but also when used with a working online connection.
  Without the plugin the quiz reports timestamps correctly