monitor: Add a random delay of maximum 60 seconds to all monitor cron jobs to avoid high load at the first second of every minute.

some jio folders are not needed anymore, webdav is only needed for config folder.
Report results are placed in documents folder so they will not be synced automatically (we can get then when needed)
Use UTC timezone in json result instead of local time.

/reviewed-on nexedi/slapos.toolbox!26

/reviewed-on nexedi/slapos.toolbox!25

/reviewed-on nexedi/slapos.toolbox!24

  Follow up nexedi/erp5@ccbf9007

/reviewed-on !20

/reviewed-on nexedi/slapos.toolbox!22

/reviewed-on nexedi/slapos.toolbox!21

use shred path as parameter and print stderr message when shred command fail

/reviewed-on nexedi/slapos.toolbox!18

/reviewed-on nexedi/slapos.toolbox!16

/reviewed-on nexedi/slapos.toolbox!15

/reviewed-on nexedi/slapos.toolbox!14

Documentation on it should be provided on slapos.libnetworkcache.

  File can be empty for whatever reason, so handle it in the same way the file don't exist.

Prevent the method to loop indefinitely

/reviewed-on nexedi/slapos.toolbox!12

  In distribution systems, it is possible that master didn't indexed the Software Installation
  when we check, this change will consider we don't know the state of the Software Installation on
  this stage. The code will retry later anyway.

  Update the tests after the fix on the code, as the map now contains all the tests form all the groups

 This bug was preventing to get a single test per group (computer) 
 per time. Causing multiple tests run on the same computer and no
 tests run on others.