spacemanager: Fix various error recovery scenarios

The patch fixes several related issues in space manager:

- The code used to delete a file reservation when the mover reported
  a failure. However whether such a file is actually deleted depends
  on what the door does. If the door deletes it, the space manager
  will be notified and the file can be deleted at that point.

  The special case that exists is if the mover failure was caused by the
  pool being unable to register the location in the name space. When
  such a file is deleted it would only get a name space delete notification,
  and no pool remove file notification. To account for this case, the
  pool leaves a file for which the mover reported an error in the
  transferring state. If the name space entry is deleted, such an entry
  is removed. If the file is not deleted, the other fixes of this
  patch will address it eventually.

- The code used to assume that a file that was in transferring
  would either get a DoorTransferFinished notification or be deleted.
  There is however no guarantee that this happens for non-srm uploads,
  such as when the door doesn't delete on failed upload. The client
  may even think the transfer is successfull if no control channel is
  used (eg http and xrootd). Such a file is perfectly readable, but
  stayed in transferring in space manager.

  This patch addresses this problem by extending the background check
  of files that have stayed in transferring for more than 24 hours:
  rather than just deleting reservations for deleted files, the code
  now also detects flushed and completed files and updates the reservation
  accordingly.

- The patch changes how we react to notifications that a name space entry
  is deleted: Before, we deleted the reservation if the file was marked
  flushed. For other states we assumed we would eventually get a pool
  remove file notification: However if the pool failed to register the
  location, we will never get such a notification. This scenario is
  quite likely if the name space entry is deleted during upload.

  The patch addresses this problem by deleting a transferring reservation on
  the name space delete notification. The downside is that we have some
  space allocated for the file on the pool that isn't explicitly linked
  to a reservation in space manager, but since the name space entry got
  deleted, the file on the pool will soon get deleted too.

- The patch also refines how we react to notifications for flushed files: if the
  reservation was in transferring, it is now considered complete.  Before the
  flush notification was simply ignored. This could both happen for lost
  DoorTransferFinished notification, of if the flush notification managed to
  overtake the DoorTransferFinished notification (unlikely).

Target: trunk
Request: 2.11
Request: 2.10
Request: 2.9
Require-notes: yes
Require-book: yes
Acked-by: Dmitry Litvintsev <litvinse@fnal.gov>
Patch: https://rb.dcache.org/r/7519/
(cherry picked from commit c59f61eb89d04948f7e8172b15cbd8288778533c)
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
(cherry picked from commit 7c43c2ad6a6d6209625ee78d6745a5f8c531d7a3)
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
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
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)
Merge pull request #1146 from gbehrmann/fix/2.9/rb7531

poolmanager: Fix full pool detection for WASS
Merge pull request #1137 from gbehrmann/fix/2.9/rb7530

Upgrade to Milton 2.6
Merge pull request #1132 from kofemann/nfs-no-multipath-2.9

pool: reorder ip addresses returned to NFS client
Merge pull request #1124 from gbehrmann/fix/2.9/rb7519

spacemanager: Fix various error recovery scenarios
[maven-release-plugin] prepare release 2.9.17
[maven-release-plugin] prepare for next development iteration