Added the test to verify title on /explore

Added the test_explore_title to address #48
You want to assert that the displayed page title matches what you expect. It's also not great to compare identical asserts- even if one came from the home page. It would be better to assert.true that the _page_title_is_visible, and/or to assert.equal that the page title matches the words you expect. I've sent you details on this.