testSetDsetFilesStatus.1

Add change dbs dataset file status fix 5204 (#5243)

* add setdataset.py for #5204

* refactor and add setfiles

* add Content-type arg to HTTPRequests

* setdataset to use contentType

* rename commands to setdatasetstatus setfilestatus

* add autocomplete

* list of LFNs not supported yet

* some pylint and pep8

* add logging for setfilestatus