Rename "Associated Entity" to Event

[joemcl]

At ~/civicrm/vol/#/volunteer/manage, there is a column named 'Associated Entity' for a Volunteer Project. Rename this to Event, unless there is another Entity to which a Volunteer Project can relate.

[ginkgomzd]

Yes, I think at this point, this would be a good change.
The only other entity type that we had in mind was another project: for implementing sub-projects. There has not been any requests for this that I can recall.