Fix splitting page issues

Duplicate argument keys cause the object returned to the reqmgr
to be an array. Make sure that there are no duplicate keys,
also display the correct values for EventAwareLumiBased splitting.
Also fix modification of max time for merge.

Fixes #4409
Fix display of output datasets

Datasets produced by output modules that are never stored in merged
area were still reported by the listOutputModules function of WMWorkload.
Fix that by adding a flag that clearly marks transient and permanent
output.

Fixes #4422
Fix JSON missing lumi function

It was broken due to improper testing and old couchdb version.

Fixes #4338
Expose AutoApprove sites to ReqMgr

Also allow modification of move/replica subscriptions for custodial
and give a more descriptive parameter to the priority option.

Fixes #4356
Merge pull request #4426 from dballesteros7/HG1303-dballest

HG1303 ReqMgr