Standardize ID formats to have hyphen as component separator

All ids should have all their components separated by hyphen.

Before it was only some of them. For example, session id was "n123-1", but
event id was "n123". Now its standardised so event/media id is "n-123"

In turn, this means that session id is "n-123-1".

This makes more logical sense, because we see "event type" as the first
level of grouping, "event" as the second level, and "session" as the third.

In other words:

1. Event type id: n
2. Event id: n-1
3. Session id: n-1-1

Original issue reported on code.google.com by mjc1...@gmail.com on 12 Apr 2009 at 3:51

marcardar / transcriptstudio-isha

Standardize ID formats to have hyphen as component separator #129