Fix crash on successful import email

app/views/mailers/import_mailer/completed.html.erb

@@ -1,5 +1,5 @@
 <p class="subtitle">Your import of <%= @account.name %> is complete!</p>
 
-<p><%= link_to "Go to your account", landing_url(script_name: account.slug) %></p>
+<p><%= link_to "Go to your account", landing_url(script_name: @account.slug) %></p>
 
 <p class="footer">Need help? <%= mail_to "support@fizzy.do", "Send us an email" %>.</p>

app/views/mailers/import_mailer/completed.text.erb

@@ -1,3 +1,3 @@
 Your import of <%= @account.name %> is complete!
 
-Here's the URL: <%= landing_url(script_name: account.slug) %>
+Here's the URL: <%= landing_url(script_name: @account.slug) %>

test/mailers/import_mailer_test.rb

@@ -0,0 +1,15 @@
+require "test_helper"
+
+class ImportMailerTest < ActionMailer::TestCase
+  test "completed" do
+    email = ImportMailer.completed(identities(:david), accounts(:"37s"))
+
+    assert_emails 1 do
+      email.deliver_now
+    end
+
+    assert_equal [ "david@37signals.com" ], email.to
+    assert_equal "Your Fizzy account import is done", email.subject
+    assert_match accounts(:"37s").slug, email.body.encoded
+  end
+end