Give - Gift Aid 2.0.0

* New: Added the {gift_aid_status} email tag to more easily see who opted in to Gift Aid.
* New: Added the {gift_aid_ address} email tag for quick reference via email if the donor opted-in to Gift Aid.
* Tweak: Improved loading of default images to be SSL friendly for sites that go from http to https when using Gift Aid.
* Fix: Resolve security issue potentially allowing other donors to view other donor's gift aid declaration forms.

* Important: This update requires Give 2.2.0+ to function properly. Please update to Give Core 2.2.0+ prior to updating this add-on.
* Fix: Resolve issue with hard coded loading of Gift Aid logo image conflicting with Google and Apple Pay.

* Fix: Resolve condition checking whether Billing Country is the UK.