xrootd: Add support for kXR_locate, kXR_query and kXR_set

kXR_locate always returns the door or pool itself, no matter whether the file
exists or not. This avoids an extra name space lookup. It is unknown whether
the argument to kXR_locate contains the opaque information, thus whether the
pool can rely on the uuid being present.

kXR_set is only implemented for appid.

kXR_query is implement for kXR_Qconfig and kXR_Qcksum. In pools we again have
the issue that the spec doesn't define whether the path contains the opaque
info.  The patch speculatively looks for the uuid and returns the checksum if
found - otherwise the client is redirected to the door.

The behaviour on kXR_open is altered slightly to return clients with missing
uuid or invalid uuid back to the door rather than return an authorization
error. The client likely just uses an outdated uuid or wants to open a second
file.

Target: trunk
Require-notes: yes
Require-book: yes
Acked-by: Paul Millar <paul.millar@desy.de>
Patch: http://rb.dcache.org/r/6565/
gplazma2-xacml: revert version of opensaml

The privilege xacml client is incompatible with the newer opensaml library.
In particular, the client bootstrap method calls a method which is missing
in the newer version.

Restores opensaml to 2.4.1 (last compatible).  Also eliminates unused opensaml1 library.

Target: master
Request: 2.8
Patch: http://rb.dcache.org/r/6581/
Bug: http://rt.dcache.org/Ticket/Display.html?id=8244
Requires-book: no
Requires-notes: no
Acked-by: Paul
Revert "Revert "packages, fhs: fix saxon includes/excludes expression""

This reverts commit 358648b0c13fe7e553de43125f7c355938e67732.

The saxon changes were unrelated to the xacml/opensaml problem
gplazma-xacml: remove dependency on org.apache.xalan

There is a xalan implementation which ships with Java.  This dependency does not seem necessary.

We now have all saxon jars in a saxon subdirectory, and no other XSLT libraries on the classpath.

Side benefit is that we can use datanucleus-xml 3.2.1 (without the fix I provided) if needed.

Target: master
Request: 2.8
Request: 2.7
Request: 2.6
Patch: http://rb.dcache.org/r/6582/
Require-book: no
Require-notes: no
Acked-by: Tigran
Log fatal errors when fetching pool monitor

Target: trunk
Require-notes: no
Require-book: no
Acked-by: Paul Millar <paul.millar@desy.de>
Patch: http://rb.dcache.org/r/6586/
nfs-proxy: add support for open-less read requests

in a production we observe situations, where client
decides to perform IO through MDS (door) with
all-zero stateid. Such behavior is  allowed by
rfc5661 (#8.2.3) and should be supported
to keep clients happy.

Acked-by: Gerd Behrmann
Target: master, 2.8, 2.7
Require-book: no
Require-notes: no