Add method to check that a page is already open
Add verifyResponse() call to shouldBeOpen()
Change name to isOpen()
Make return boolean, add initial specs
Add acceptance criteria for "Verifying if a page is open" feature.
Merge remote-tracking branch 'aderuwe/patch-1' into feature/29-verifying-if-a-page-is-open
Enable first implemented scenario.
Make sure the file name matches the class name.
Fix the expected message.

The exception will actually be coming from the context.
Implement url verification.
Document page verification methods.
Clarify scenario titles.
Merge pull request #30 from jakzal/feature/29-verifying-if-a-page-is-open

[Feature] Verifying if a page is open