Fix matched_contributions association on match
Create total_pledged method on match

It's include pledged + original contributions
Notify observers when complete a match

On MatchFinisher.
Create match_ended notification views
Notify match owner that match has ended
Create notifications views for match been met
Create notifications views for contribution match was met
Create observer method on match to send notifications
Move instance method to class method on match finisher
Notify observers when remaining amount of a mach is zero
Remove unstub from match observer specs
Use only confirmed contributions on match notifications
Merge pull request #290 from neighborly/jl-new-match-notifications

Implement the new notifications for matches