use action mailer deliver_now instead of deprecated deliver

app/models/event.rb

@@ -137,7 +137,7 @@ class Event < ActiveRecord::Base
     if options[:send_mail]
       self.event_people.presenter.each do |event_person|
         event_person.generate_token!
-        SelectionNotification.acceptance_notification(event_person).deliver
+        SelectionNotification.acceptance_notification(event_person).deliver_now
       end
     end
     if options[:coordinator]
@@ -148,7 +148,7 @@ class Event < ActiveRecord::Base
   def process_rejection(options)
     if options[:send_mail]
       self.event_people.presenter.each do |event_person|
-        SelectionNotification.rejection_notification(event_person).deliver
+        SelectionNotification.rejection_notification(event_person).deliver_now
       end
     end
     if options[:coordinator]

app/models/user.rb

@@ -78,7 +78,7 @@ class User < ActiveRecord::Base
   def send_confirmation_instructions
     return false if confirmed_at
     generate_confirmation_token! unless self.confirmation_token
-    UserMailer.confirmation_instructions(self).deliver
+    UserMailer.confirmation_instructions(self).deliver_now
   end
 
   # update users call for papers and sends mail
@@ -87,7 +87,7 @@ class User < ActiveRecord::Base
       self.call_for_papers = call_for_papers
     end
     generate_password_reset_token!
-    UserMailer.password_reset_instructions(self).deliver
+    UserMailer.password_reset_instructions(self).deliver_now
   end
 
   def try_call_for_papers