Doc: Update Qt licensing documentation

Update the documentation to cover the inclusion of LGPL version 3
licensing option.

Add information about the Apache 2.0 licensed code used for the
Native style for Android.

Add information about the Wayland protocol license for Qt
Wayland.

Fix layout issues in the table describing the other licenses, as
well as a wrong license type listed for Qt Script module.

Fix a number of external links and remove links pointing to
the old download page for commercial Qt versions.

Task-number: QTBUG-41024
Task-number: QTBUG-41798
Change-Id: I203b2ace6cc379da3b0cab12b6197b35c195720c
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Sami Makkonen <sami.makkonen@digia.com>
Reviewed-by: Jani Heikkinen <jani.heikkinen@digia.com>
Reviewed-by: Topi Reiniö <topi.reinio@digia.com>