Windows and macOS installer license violations

Original Launchpad bug 1797132: https://bugs.launchpad.net/openlp/+bug/1797132

Reported by: bastian-germann (Bastian Germann).

The Windows and macOS installers contain even more license violations than bug #1795876. You redistribute the dependencies with these installers and I cannot see any license being documented other than OpenLP's own GPLv2. In general even "liberal" free software licenses like BSD or MIT require you to include the license statement in ANY redistribution, including binary distribution.