srm: Fix property chaining

Addresses the problem that the properties that should apply to
all requests types had no effect at all.

Note that the get request values were used as the base for other
requests types in the old system. This is reflected in the way
properties are chained.

Target: trunk
Require-notes: no
Require-book: no
Acked-by: Dmitry Litvintsev <litvinse@fnal.gov>
Patch: http://rb.dcache.org/r/5852/