Change "Projects" menu option to "Navigator".

The Resource navigator is the default workspace browser in CS-Studio.
It is least confusing to users if the Resource Navigator view opens
instead of Project Explorer because that is the default view in CS-Studio.
Remove unused 'Activator' class.

File must have been created automatically by Eclipse.
Update version numbers for Repository Monitor plugin and feature.
Change the Repo Monitor menu to correspond with "Navigator" view tab.
Increase delay between startup and first Repo Monitor refresh to 30sec.