Update kdewallet to 1.3.1

[purejava]

This updates kdewallet to the current version and re-enables the kdewallet functionality in integrations-linux.

As the 'split jar' problem arose for the first time, I released kdewallet 1.3.0 to fix it, but with it, not all classes of kdewallet were moved to a namespace controlled by the author, as the package name of the Java interface needs to follow the interface name of the D-Bus interface. By using @DBusInterfaceName, all interfaces can be moved to a namespace controlled by the author and thus fully avoid 'split jar' problems. This is done with kdewallet 1.3.1.

Implementing the libappindicator features for integrations-linux made it necessary to have a module-info.java. It currently lacks a KeychainAccessProvider for kdewallet to make kdewallet functionality available for Cryptomator.

Both problems are addressed with this PR.