Bug 1030552 - [Calendar] "All day" on month view is not localized for All day events r=gaye

I don't like it so much since we might update the markup structure in the future (and would need to update the tests). Also adding line breaks, white spaces and extra css classes would make the test to break.

I think this test is enough to check that we are returning all the provided data and that the all day event has the `data-l10n-id="hour-allday"`. Even tho it doesn't ensure that the elements are built exactly the way we expect..

PS: I copied this structure from the other template tests (eg: https://github.com/mozilla-b2g/gaia/blob/master/apps/calendar/test/unit/templates/month_test.js)