Allow Administrators to add bubble help for custom success events

[#1]

In SiteCatalyst, predefined success events like Orders & Revenue come with help text which is accessed through the "?" bubble help in the metric column.  However, these are not available for custom success events.  It would be cool if administrators could put a one senetence description of what each success event is (define it) in the success event admin console screen next to each event and have end-users see that sentence when they click the "?" in th emetric column.  That way every metric woudl have a "?" icon and all end-users coudl be better informed about what the metric is, when it is set, how it shoudl be used, etc...