nfs: fix NPE on door reboot

handle PoolPassiveIoFileMessage message comming from a pool
even if door did not initialize it. Happend on door restarts
during heavy IO load.

Acked-by: Paul Millar
Target: master
Require-book: no
Require-notes: no
(cherry picked from commit e4f8fc5c9528e40ca7e27083c6ae92a38d5a9de0)
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
 pool: reorder ip addresses returned to NFS client

according to NFS spec pool client can select a best matching IP
address from the list available IP addresses of the pool.

Nevertheless, current client implementation in RHEL-6 takes first
one from the list and, some times, makes a wrong choice for mutihomed
pools.

This change will put 'expected correct' interface as a first element
of the returned list.

Ticket: #8404
Acked-by: Gerd Behrmann
Target: master, 2.11, 2.10, 2.9, 2.8, 2.7, 2.6
Require-book: no
Require-notes: no
Upgrade to Milton 2.6

Appears to be working. Solves the problem where proxied vector reads cause the entire
file to be written to local disk. Instead only the actual data that is to be returned
to the client is buffered. If this is more than 100 KB, that data is buffered on local
disk. The file is deleted after successful return of the data.

There are still problems though: In case of failures reading the data from the pool,
the temporary file is not deleted. The entire file is still downloaded from the pool
to the door (even when only the requested data is buffered), and the multi-range writer
in Milton is extremely inefficient as it processes one byte at a time (it fails to
override the multi-byte write methods).

The new version supports using cookies to remeber when a client has already logged in.
I disabled this feature for now.

Target: trunk
Request: 2.11
Request: 2.10
Request: 2.9
Request: 2.8
Request: 2.7
Request: 2.6
Require-notes: yes
Require-book: no
Acked-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Patch: https://rb.dcache.org/r/7530/
(cherry picked from commit b0f88c5080926e867ca644087a4e75e7c077bf00)

Conflicts:
	pom.xml

(cherry picked from commit a510d8109287fce0b825db266225e935ac2e3919)

Conflicts:
	pom.xml

(cherry picked from commit 27783b3575665704b147e36e8bf4c189efbff6c2)

Conflicts:
	pom.xml

(cherry picked from commit 04841d4e3e88c15fbd4c3ad213a941e74aa26321)

Conflicts:
	pom.xml

(cherry picked from commit 2bad5586d7c435effd3cb98ccc4e3fc5c87a7857)

Conflicts:
	pom.xml

(cherry picked from commit 0ee48ba1f22a33c5b6205e7cda957d0e41d55c1f)

Conflicts:
	pom.xml
poolmanager: Fix full pool detection for WASS

When a file cannot fit within the free plus removable space without
crossing the pool gap, a pool is considered full. WASS erroneously
used the decayed removable space in this check. This meant that
if all pools had very fresh files, they could all be considered
full even though there are plenty of removable files. This patch
changes the check to consider all removable space of a pool. The
decayed removable space is only used when weighting the random
selection.

Target: trunk
Request: 2.11
Request: 2.10
Request: 2.9
Request: 2.8
Request: 2.7
Request: 2.6
Ticket: http://rt.dcache.org/Ticket/Display.html?id=8390
Require-notes: yes
Require-book: no
Acked-by: Christian Bernardt <christian.bernardt@desy.de>
Patch: https://rb.dcache.org/r/7531/
(cherry picked from commit 42e31b5f935af4f3220aa29f2e51e8ea2c0bd146)

Conflicts:
	modules/dcache/src/main/java/org/dcache/poolmanager/WeightedAvailableSpaceSelection.java
	modules/dcache/src/test/java/org/dcache/poolmanager/WeightedAvailableSpaceSelectionTest.java
Merge pull request #1149 from gbehrmann/fix/2.6/rb7531

poolmanager: Fix full pool detection for WASS
Merge pull request #1140 from gbehrmann/fix/2.6/rb7530

Upgrade to Milton 2.6
Merge pull request #1131 from kofemann/no-nfs-multipath-2.6

 pool: reorder ip addresses returned to NFS client
Merge pull request #1118 from kofemann/fix-nfs0noe-2.6

nfs: fix NPE on door reboot
[maven-release-plugin] prepare release 2.6.40
[maven-release-plugin] prepare for next development iteration