WL-3003 Service and test updated to allow hidden.

We now store hidden flag although there is no UI for it yet and we still render it.
Tidy up incorrect JavaDoc.
WL-3003 Don't display hidden redirects in UI.
WL-3003 Add UI for hidden redirects.

This shows hidden redirects as such and allows new redirect to be created as hidden.
Tidy up import
WL-3003 Correctly send true as the hidden value.
WL-3003 Allow redirect to have title empty.

There is no point in having a title on a redirect as it's not show in the sub site menu. We now make sure that the title of a redirect is null and this ensures it's also at the end of the Redirect list.
Add titles for the labels in the add redirect form.
Merge pull request #16 from ox-it/WL-3003

WL-3003 Allow redirects to be hidden.