#562 - extended backup state by a third state "unknown":

...ava/de/deadlocker8/budgetmaster/backup/BackupService.java

...java/de/deadlocker8/budgetmaster/backup/BackupStatus.java

...n/java/de/deadlocker8/budgetmaster/backup/BackupTask.java

...ava/de/deadlocker8/budgetmaster/backup/GitBackupTask.java

...a/de/deadlocker8/budgetmaster/backup/LocalBackupTask.java

...e/deadlocker8/budgetmaster/backup/LocalGitBackupTask.java

.../deadlocker8/budgetmaster/backup/RemoteGitBackupTask.java

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

src/main/resources/languages/base_de.properties

src/main/resources/languages/base_en.properties

src/main/resources/templates/settings/settingsMacros.ftl