Fix #4571: Show banner when email verification is required.

* Show a banner if the user is restricted because they signed up from a
  proxy or VPN.

* Add an option to resend the confirmation email if your account has an
  unverified email address.

app/controllers/emails_controller.rb

@@ -21,7 +21,7 @@ class EmailsController < ApplicationController
     end
 
     if @user.errors.none?
-      flash[:notice] = "Email updated"
+      flash[:notice] = "Email updated. Check your email to confirm your new address"
       UserMailer.email_change_confirmation(@user).deliver_later
       respond_with(@user, location: settings_url)
     else
@@ -31,10 +31,27 @@ class EmailsController < ApplicationController
   end
 
   def verify
-    @email_address = authorize EmailAddress.find_by_user_id!(params[:user_id])
-    @email_address.update!(is_verified: true)
+    @user = User.find(params[:user_id])
+    @email_address = @user.email_address
 
-    flash[:notice] = "Email address verified"
-    redirect_to @email_address.user
+    if @email_address.blank?
+      redirect_to edit_user_email_path(@user)
+    elsif params[:email_verification_key].present?
+      authorize @email_address
+      @email_address.update!(is_verified: true)
+      flash[:notice] = "Email address verified"
+      redirect_to @email_address.user
+    else
+      authorize @email_address
+      respond_with(@user)
+    end
+  end
+
+  def send_confirmation
+    @user = authorize User.find(params[:user_id]), policy_class: EmailAddressPolicy
+    UserMailer.welcome_user(@user).deliver_later
+
+    flash[:notice] = "Confirmation email sent to #{@user.email_address.address}. Check your email to confirm your address"
+    redirect_to @user
   end
 end