count backups without schedules for quota usage (itacloud-3271)
Merge branch 'feature/itacloud-3271' into 'develop'

Feature/itacloud 3271 (usage backup_storage calculation)
Increase timeout for long-running backups

- ITACLOUD-3273
Set agreed_sla instance field on provisioining
Expose IntsanceLicenses in django admin
Clean up documentation