Add redirect to response

Now a relocation can be done, by calling redirect with the URL you want
relocate to.
This will set the Location header and set the status code to 302.

lib/zero/response.rb

@@ -67,5 +67,14 @@ module Zero
       self.header['Content-Type'] = value
     end
 
+    # Sets the Location header to the given URL and the status code to 302.
+    # 
+    # @param [String] location Redirect URL
+    #
+    def redirect(location)
+      self.status = 302
+      self.header['Location'] = location
+    end
+
   end
 end

spec/unit/response/response_spec.rb

@@ -125,4 +125,14 @@ describe Zero::Response do
     end
   end
 
+  describe '#redirect' do
+    it "sets the status to 302 and the given Location URL in header" do
+      subject.redirect 'http://foo.bar/relocated/thingy'
+      value = subject.to_a
+
+      value[0].should eq(302)
+      value[1]['Location'].should eq('http://foo.bar/relocated/thingy')
+    end
+  end
+
 end