enumerateNamespace
Checks if the matcher will match all of the keys in a given namespace. This will always return true if a wildcard character is in use (e.g. if matcher was created with "standard::" and @ns is "standard", or if matcher was created using "" and namespace is anything.)
TODO: this is awkwardly worded.
Return
true if the matcher matches all of the entries in the given @ns, false otherwise.
Parameters
ns
a string containing a file attribute namespace.