minor changes
errror handling and logging

- CHG: moved Error event to separate types
- CHG: log messages are cloned in AggregateLogger and DelegateLogger now
web interface, data(bser), extension/helper methods and NHibernate

- ADD: web interface needs valid user for login now
- ADD: entity repository framework
- ADD: started to implement NHibernate version of IAppServerDatabase
service
- ADD: GetColumns() and TryGetTableNameAndSchema() helper methods