Fix/3.x/3257 broken config validation

  Fixes #3257 : config validation
    
    Fixed the issue that not a lot of config validation is done. It also fixes the issue
    that in some cases instart of shutting down the node, due to the config conflict, a
    seperate cluster is created.
    
    This patch doesn't contains logic for structural checking of conflicts for map/queue
    etc. But it does contain all the infrastructure.
    
    It also contains the feature where a user can provide a 'token' to that needs to be
    the same on all members. E.g. filepath or other configuration settings. This can be
    done through the hazelcast.application.validation.token system property.