Rename friendship_notification to follow_notification

app/controllers/follows_controller.rb

@@ -26,7 +26,7 @@ class FollowsController < ApplicationController
       flash[:error] = t ".limit_exceeded"
     elsif follow.save
       flash[:notice] = t ".success", :name => @friend.display_name
-      UserMailer.friendship_notification(follow).deliver_later
+      UserMailer.follow_notification(follow).deliver_later
     else
       follow.add_error(t(".failed", :name => @friend.display_name))
     end

app/mailers/user_mailer.rb

@@ -119,7 +119,7 @@ class UserMailer < ApplicationMailer
     end
   end
 
-  def friendship_notification(follow)
+  def follow_notification(follow)
     with_recipient_locale follow.following do
       @follow = follow
       @viewurl = user_url(@follow.follower)

config/locales/en.yml

@@ -1661,7 +1661,7 @@ en:
       header_html: "%{from_user} has sent you a message through OpenStreetMap with the subject %{subject}:"
       footer: "You can also read the message at %{readurl} and you can send a message to the author at %{replyurl}"
       footer_html: "You can also read the message at %{readurl} and you can send a message to the author at %{replyurl}"
-    friendship_notification:
+    follow_notification:
       hi: "Hi %{to_user},"
       subject: "[OpenStreetMap] %{user} followed you"
       followed_you: "%{user} is now following you on OpenStreetMap."