* feat: new metadata backup endpoint
* feat: added restore/sql API endpoint
* fix: content-type is multipart/mixed, part names are kv and sql
* fix: changed multipart manifest to buckets and made it .json
* feat: added lock for backing up sqlite and bolt dbs
* fix: use read lock instead of write lock on kv during backup
* fix: use filepath.Join for temp dirs
* feat(backup): `influx backup` creates data backup
* feat(backup): initial restore work
* feat(restore): initial restore impl
Adds a restore tool which does offline restore of data and metadata.
* fix(restore): pr cleanup
* fix(restore): fix data dir creation
* fix(restore): pr cleanup
* chore: amend CHANGELOG
* fix: restore to empty dir fails differently
* feat(backup): backup and restore credentials
Saves the credentials file to backups and restores it from backups.
Additionally adds some logging for errors when fetching backup files.
* fix(restore): add missed commit
* fix(restore): pr cleanup
* fix(restore): fix default credentials restore path
* fix(backup): actually copy the credentials file for the backup
* fix: dirs get 0777, files get 0666
* fix: small review feedback
Co-authored-by: tmgordeeva <tanya@influxdata.com>