make it easy to deal with tails

[belforte]

this is a general container for various changes that will help users.
List below is work in progress. Updated as of August 2024. RIght before Dario leaves CRAB !

• a command to wrap up current task and capitalize on work done so far and ensure there's info for completing "later" - done : crab kill + crab recovery
• a wrapper to make simple (automatic?) to create and run recovery tasks, including "more data became available" - Done with crab recovery
• make sure recovery task can be run also for tasks older than 1 month - We decided not to do/allow this.
• improve automatic retries - Left for the future
• need to add last missing piece to crab recovery: recovery tasks submitted with FileSplitting - add FileSplitting to use cases covered by crab recovery CRABClient#5330