Label dumper

This turns on StarTeam keep-alive because I kept getting disconnected from our StarTeam server. I have not been disconnected since turning on keep-alive, so I think it resolves the issue. It does not appear to cause any harm.

There was also a bug that prevented the root view from being imported when using all-views mode.

This also adds a label dumper program which can be used with git-starteam-merges to reconstruct merge history.