add "weekly" backup to new backup system without keep 7 days of retentions
If we want to have weekly backup on "new"cpanel backup system, we need to make daily run everyday.
If this way, we need to keep "7" retentions of daily backup that will cost us a lot to upgrade backup drives
We just want to keep:
- daily => one retention so if server crashes, we have "latest" backup to restore
- weekly => one retention too, to let client could find old files when they make mistakes on file edition and do not notice it in time
Most of the time, weekly is the most useful backup files for clients coz 95% of them notice problems days later, so daily is usually not useful but just for server disaster use.
Also, we do NOT want client to restore 7 DAYS of backup from MON-SUN for just trying to find what they want, which might cause server problems.
so, to resolve these issues, please add a function to let us decide "how many retentions" too keep on each frequency.