def find_campaigns_by_subject(subject)#-- TODO: Refactor this method
      arr = []
      #return campaigns.find {|campaign| subject == campaign.subject} if params[:single] 
      campaigns.each { |campaign| arr << campaign if campaign.subject == subject }
      arr
    end
def find_campaigns_by_subject(subject)#-- TODO: Refactor this method
      arr = []
      #return campaigns.find {|campaign| subject == campaign.subject} if params[:single] 
      campaigns.each { |campaign| arr << campaign if campaign.subject == subject }
      arr
    end
This method finds campaigns by a given subject, since the subject isn't unique, it returns an collection of
Campaigning::Campaign object.

*Return*:

*Success*: Upon a successful call, this method will return a collection of Campaigning::Campaign objects.

Campaign FOUND: If it found any campaign with the given subject it will return a collection of Campaigning::Campaign that match the criteria.

Campaign NOT FOUND: If it doesn't found a campaign with the given subject it will return an empty array.

*Error*: An Exception containing the cause of the error will be raised.