Add fed shares scanner batched cronjob

[mmattel]

What Needs to be Documented?

Upcoming changes from core:
owncloud/core#37391 (Add fed shares scanner batched cronjob)

Text change:
WARNING: incoming-shares:poll has been deprecated and replaced by periodic external shares cronjob. Please check Federated Cloud Sharing settings and documentation.

Command change:

# required
occ config:app:set files_sharing cronjob_scan_external_enabled --value yes

# optionaly 
occ config:app:set files_sharing cronjob_scan_external_min_login --value 14400
occ config:app:set files_sharing cronjob_scan_external_min_scan --value 3600
occ config:app:set files_sharing cronjob_scan_external_batch --value 100

Where Does This Need To Be Documented?

occ command set

Why Should This Change Be Made? (Optional)

New and deprecated commands

What Type Of Content Change Is This? (Optional)

• New Content Addition
• Old Content Deprecation
• Existing Content Simplification
• Bug Fix to Existing Content

Which Manual Does This Relate To? (Optional)

• Admin Manual
• Developer Manual
• User Manual
• Android
• iOS
• Branded Clients
• Desktop Client
• Other

Note: this is most likely for 10.5 only ! To prepare, a new branch "10.5" needs to be created (anyway...)

@mrow4a @pmaier1

[mrow4a]

@mmattel might be useful owncloud/core#37391 (comment)