Gwbackupy

- Enh 38: kill signals handling

- Enh: namespace refactoring `gwb` -> `gwbackupy`
- Enh 22: restore missing Gmail messages (`--restore-missing`)
- Bug: fixed date filters parsing

**Local file Storage BC break**

- Enh: temporary file based creation for minimize invalid files states
- Enh: Separation of service parameters for easy reusability in another python library or package
- Enh 13: Self managed versioned file storage with extendable custom storage interface (eg. for database)
- Enh 9: Dry mode
- Enh: Cleaner log messages
- Enh 12: OAUTH supports for free plans
- Enh 18: Quick syncing gmail backup mode

- Enh 8: service account json key file support
- Enh 6: Gmail restore by message ID

- Enh 1: write message.json only if it changes - gmail backup. (kamarton)
- Enh 2: --log-level parameter
- Enh 3: more logs, remove print() usage
- Fix: gmail restore CHAT labels (fix with skipping)
- Enh 4: memory optimization
- Enh: local files scanning speed optimization

Software version fix and automatism