LMS-2465 Flexible import/upload: Support uploading a merged Excel file

...ce/java/ch/systemsx/cisd/common/parser/TabFileLoader.java

.../ch/systemsx/cisd/etlserver/SampleRegisteringDropbox.java

openbis/.settings/.gitignore

openbis/.settings/org.eclipse.jdt.ui.prefs

openbis/results.txt

.../cisd/openbis/generic/shared/parser/ExcelFileSection.java

...bis/generic/shared/parser/SampleUploadSectionsParser.java

...ugin/generic/client/web/client/IGenericClientService.java

...generic/client/web/client/IGenericClientServiceAsync.java

...lugin/generic/client/web/server/GenericClientService.java

...lient/web/server/parser/MaterialUploadSectionsParser.java

...msx/cisd/openbis/plugin/generic/server/GenericServer.java

...sd/openbis/plugin/generic/server/GenericServerLogger.java

...sx/cisd/openbis/plugin/generic/shared/IGenericServer.java

...penbis/plugin/generic/shared/IGenericServer.java.expected

.../plugin/screening/client/web/client/application/Dict.java

...eening/client/web/client/application/ScreeningModule.java

...ent/application/detailviewers/LibraryImportComponent.java

...lugin/screening/client/web/public/screening-dictionary.js

.../plugin/screening/client/web/server/LibraryExtractor.java