* new(sync): implement sync subcommand (WIP)
TODO
- update CHANGELOG
- refactor sync func
* fix(sync): add pull (only fast forward)
* update(test): use sync command
The first sync from 2nd device didn't work, maybe due to that it is the
first push.
* refactor: separate push and pull to funcs
* refactor: change merge analysis match order
* refactor: add logs
* update: CHANGELOG
* fix: CHANGELOG was wrong
- return Err instead of new object when there is no STORAGESFILE
- setup empty DEVICESFILE and STORAGESFILE at repository initialization
- update readme