added spec for #path

spec/unit/request/path_spec.rb

@@ -0,0 +1,7 @@
+describe Zero::Request, '#path' do
+  subject { Zero::Request.new(env) }
+  let(:path) { '/foo' }
+  let(:env) { EnvGenerator.get(path) }
+
+  its(:path) { should == path }
+end