change station, add jdbcStationDaoImpl, add ScheduleDao
some changes in util, ticket, train, user classes
change Client readResponse to return empty response instead of null, change handlers map in server
add jdbcTicketDaoImpl, scheduleDao; some miscelanous in PassengerDaoImpl, UserDaoImpl
 add tests for schedule, station, user DaoImpl; add jdbcRouteDaoImpl, TrainDaoImpl
add RouteDaoImplTest -- failed because of db constraint violations -- need to be fixed
add classes to provide login, register, find all stations, find trains between stations and time interval
add RzdException and WrongDateException
add TrainSearchItem to provide trains search
add handlers for search stations, trains; some refactoring in loginHandler and RegisterHandler