Run E2E tests against HTTPS base URL

Since we've configured our site to redirect to https by default, some
tests which use the base URL were failing because they were expecting
"http://whatever" and getting "https://whatever". Now that we're using
HTTPS everywhere, it only makes sense to test against HTTPS, too.
Use modalService for confirmations instead of JS

Instead of the Javascript confirm() or alert() functions, we'll use the
modalService dialogs. They look better, and they're more customizable
(we can set button texts to "Cancel" and "Archive" instead of "Cancel"
and "OK", for example). They are also easier to use in E2E testing.