#598 - renamed Database to InternalDatabase

.../de/deadlocker8/budgetmaster/database/DatabaseParser.java

...de/deadlocker8/budgetmaster/database/DatabaseService.java

...e/deadlocker8/budgetmaster/database/InternalDatabase.java

...adlocker8/budgetmaster/database/model/BackupDatabase.java

...er8/budgetmaster/database/model/v4/BackupDatabase_v4.java

...er8/budgetmaster/database/model/v5/BackupDatabase_v5.java

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

...deadlocker8/budgetmaster/settings/SettingsController.java

...ocker8/budgetmaster/unit/database/DatabaseImportTest.java

...ocker8/budgetmaster/unit/database/DatabaseParserTest.java

...er8/budgetmaster/unit/database/DatabaseParser_v5Test.java