webapi man page: clarify that the name parameter semantics
webapi man page: clarify that the name parameter semantics

With duplicate names allowed in the PMNS, the name parameter
returns _one_ of the names of the associated metric, a la
pmNameId(3).

andyvand/cygpcpfans,prasincs/pcp,adfernandes/pcp,adfernandes/pcp,prasincs/pcp,aeg-aeg/pcpfans,prasincs/pcp,prasincs/pcp,edwardt/pcp,tjanez/pcp,andyvand/cygpcpfans,tjanez/pcp,prasincs/pcp,wuliming/pcp,wuliming/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,edwardt/pcp,tjanez/pcp,wuliming/pcp,andyvand/cygpcpfans,andyvand/cygpcpfans,prasincs/pcp,edwardt/pcp,adfernandes/pcp,adfernandes/pcp,andyvand/cygpcpfans,andyvand/cygpcpfans,andyvand/cygpcpfans,wuliming/pcp,aeg-aeg/pcpfans,andyvand/cygpcpfans,aeg-aeg/pcpfans,aeg-aeg/pcpfans,edwardt/pcp,aeg-aeg/pcpfans,edwardt/pcp,edwardt/pcp,tjanez/pcp,tjanez/pcp,aeg-aeg/pcpfans,wuliming/pcp,tjanez/pcp,aeg-aeg/pcpfans,edwardt/pcp,wuliming/pcp,edwardt/pcp,prasincs/pcp,tjanez/pcp,tjanez/pcp,wuliming/pcp,prasincs/pcp,aeg-aeg/pcpfans,wuliming/pcp