big refactoring: classes related to tags

.../deadlocker8/budgetmaster/database/DatabaseParser_v3.java

...eadlocker8/budgetmaster/database/legacy/LegacyParser.java

...dlocker8/budgetmaster/reports/ReportGeneratorService.java

...er8/budgetmaster/reports/columns/ReportColumnService.java

...de/deadlocker8/budgetmaster/services/DatabaseService.java

...adlocker8/budgetmaster/services/FilterHelpersService.java

.../de/deadlocker8/budgetmaster/services/HelpersService.java

...a/de/deadlocker8/budgetmaster/services/ImportService.java

src/main/java/de/deadlocker8/budgetmaster/tags/Tag.java

.../java/de/deadlocker8/budgetmaster/tags/TagRepository.java

...n/java/de/deadlocker8/budgetmaster/tags/TagScheduler.java

...ain/java/de/deadlocker8/budgetmaster/tags/TagService.java

...de/deadlocker8/budgetmaster/transactions/Transaction.java

...ker8/budgetmaster/transactions/TransactionController.java

...ker8/budgetmaster/transactions/TransactionRepository.java

...e/deadlocker8/budgetmaster/transactions/Transaction_.java

...e/deadlocker8/budgetmaster/TransactionRepositoryTest.java

...deadlocker8/budgetmaster/database/DatabaseImportTest.java

...dlocker8/budgetmaster/database/DatabaseParser_v3Test.java

...e/deadlocker8/budgetmaster/database/LegacyParserTest.java