Call rspec with bundle exec

.travis.yml

@@ -6,4 +6,4 @@ install:
     docker build . -t mapknitter-exporter:latest
 
 script:
-    docker run mapknitter-exporter rspec
+    docker run mapknitter-exporter bundle exec rspec

spec/landing_spec.rb

@@ -0,0 +1,30 @@
+# Copyright 2015 Google, Inc
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require_relative "../app.rb"
+require "rspec"
+require "rack/test"
+
+describe "Mapknitter Exporter" do
+  include Rack::Test::Methods
+
+  def app
+    Sinatra::Application
+  end
+
+  it "displays Mapknitter Exporter text" do
+    get "/"
+    expect(last_response.body).to match("Mapknitter Exporter")
+  end
+end