* prevented crashing when database indexes are missing, they are now permanent instead of being created on-the-fly when loading a dictionary
* code style fixes in DictionaryDb.java
* removed some unused code
* counting the dictionaries to be loaded is no longer responsibility of the Load Button, but of the DictionaryLoader
* delete dictionary buttons are now being locked while deleting is in progress; also, a status message is displayed for better UX
* updated translations and documentation
c63d054422
