LMS-2132 Initial work on jython-based validation.

...h/systemsx/cisd/etlserver/validation/ValidationError.java

...msx/cisd/etlserver/validation/ValidationScriptRunner.java

.../systemsx/cisd/openbis/dss/client/api/cli/CommandPut.java

...msx/cisd/openbis/dss/client/api/cli/CommandTestValid.java

...sx/cisd/openbis/dss/client/api/cli/DssCommandFactory.java

...cisd/openbis/dss/client/api/gui/DataSetMetadataPanel.java

...sd/openbis/dss/client/api/gui/DataSetPropertiesPanel.java

.../openbis/dss/client/api/gui/DataSetUploadClientModel.java

...systemsx/cisd/openbis/dss/client/api/gui/UiUtilities.java

...emsx/cisd/etlserver/validation/basic-validation-script.py

...msx/cisd/etlserver/validation/invalid-data-set/.gitignore

...x/cisd/etlserver/validation/valid-data-set/valid-file.txt

...isd/openbis/dss/client/api/cli/DssCommandFactoryTest.java