Implemented sorting for data endpoint, ref #120, closes #120

...e/src/main/java/at/tuwien/endpoint/TableDataEndpoint.java

...st/java/at/tuwien/endpoint/TableDataEndpointUnitTest.java

...t/java/at/tuwien/service/QueryServiceIntegrationTest.java

...src/test/java/at/tuwien/service/QueryServiceUnitTest.java

.../src/main/java/at/tuwien/exception/SortDataException.java

.../services/src/main/java/at/tuwien/mapper/QueryMapper.java

...e/services/src/main/java/at/tuwien/querystore/Column.java

...ce/services/src/main/java/at/tuwien/querystore/Query.java

...ce/services/src/main/java/at/tuwien/querystore/Table.java

...ervices/src/main/java/at/tuwien/service/QueryService.java

.../main/java/at/tuwien/service/impl/HibernateConnector.java

...rc/main/java/at/tuwien/service/impl/QueryServiceImpl.java