LMS-1231 TableModel refactored to allow ImageTableCell. URLMethodWithParameters encoded.

.../columns/specific/data/DataSetReportColumnDefinition.java

...t/web/client/application/ui/data/DataSetReporterGrid.java

...t/web/client/application/ui/grid/AbstractBrowserGrid.java

...ch/systemsx/cisd/openbis/generic/server/CommonServer.java

...openbis/generic/shared/basic/URLMethodWithParameters.java

...generic/shared/basic/dto/DatastoreServiceDescription.java

...bis/generic/shared/basic/dto/ISerializableComparable.java

...cisd/openbis/generic/shared/basic/dto/ImageTableCell.java

...isd/openbis/generic/shared/basic/dto/StringTableCell.java

...msx/cisd/openbis/generic/shared/basic/dto/TableModel.java

.../cisd/openbis/generic/shared/basic/dto/TableModelRow.java

...bis/generic/shared/basic/URLMethodWithParametersTest.java