[keycloak-dev] Truststores

We need to be able to configure the truststore used by Keycloak when connecting to user federation providers, identity brokers and clients. Ideally this should be achievable through the admin console, but failing that we at least need to document how to create and configure a truststore manually. Further we should probably also use the same truststore for database connections. We should probably introduce a TruststoreSPI?