Fix the logic used to determine the JDK 15 assets and download links. Pre-releases are now excluded, as well as openj9 binaries. The resulting assets are final releases of hotspot builds.
Extend the gradle script with tasks that use jpackage to generate Bisq binaries. The kind of binaries generated depend on the OS where this is executed.
The packaging of binaries can be started by calling:
./gradlew --console=plain packageInstallers
from the root project folder.
