Extract counts to attributes on campaign model

Turning a sum into a database row count for speed too
Eager load related data

To reduce database queries for displaying page
Remove not found check

It was necessary as find_by_name returns nil on failure
and doesn’t raise a NotFound exception
Using name as param could cause non uniqueness problems
Paginate display

Loading thousands of links will not work
Show campaign start date
Use header space
Link to campaigns index page for admin
Fix tests for campaign lookup
Use cancan for authorization of campaigns
Show honest success/failure of generation
Fixup features for campaign pages
Merge pull request #938 from theodi/feature-campaign-reporting-improvements

Feature campaign reporting improvements