Setup: store sample demo client configuration in setup.properties.last

[nynymike]

During installation we create two clients to make facilitate testing and development: api-rp.p12 and scim-rp.jks

The information should be randomly generated, displayed at the end of the installation process, and then stored in setup.properties.last. Also, its important that the screen can be copied, because the admin will need to write these down post-installation.