Backupy

- sort database.json by key (file paths)
- write non-ascii characters in database.json without escapes
- remove unnecessary fields from config

- dry run no longer modifies main database and instead modifies a copy
- add scan only option to update database, check CRC, etc
- update command line interface
- update log format
- add verify crc on copy feature, this uses the most recently recorded CRC of the source and compares it to a freshly calculated one of the copy (therefore it could still trigger a copy error if the source file was corrupted between its last CRC recording and an update, eg using an old source with ATTR+ and moving to a fresh dest)

- Some minor new features, database changes, and bug fixes

- re-enable dst tolerance for checking file matches on both sides
- a couple of gui fixes

- Added a force posix path separator flag that can be set in the config, useful for drives shared between multiple OSs
- Fixed a lot of minor bugs (mostly with respect to CRC handling and error detection)
- Other minor improvements (GUI fixes, etc)

- Vastly improved CRC handling and bug fixes