Syntactic adjustments from @mtbc
Merge pull request #1277 from sbesson/matlab_examples_fix

Matlab examples fix
DB 4.1-4.4 upgrade script fix from Bernhard Hollaender

"There is bug in the screen-plate-well model migration function in the
SQL script for the Omero4.1 to 4.4 database migration.

There is a statement that converts the annotationlinks from
screenacquisitionannotationlink to plateacquisitionannotationlink. The
where clause is wrong, it needs to be the
screenacquisitionannotaionlink.parent field that is looked up in the
plateacquistion table as id."
Provide SYSTEM priority thread executor for reload (See #11033)

Along with the other resource contention issues seen under 11033,
a number of imports performing stats calculation led to SM.reload()
blocking. Since this is called by getEventContext() all of the
joinSessions from OMERO.web were blocked, completely breaking the
client.

Now, a special `ExecutorService` is available for high-priority
threads. It will grow without bound, but threads will be cached
and reaped as necessary. A better implementation might try to
use a single thread pool, but save a few slots of system threads.
Fix DummyExecutor
Use btm prepared statement cache (See #11033)

Suggestion on the list was that the time to remove
the 1K or 10K uncached prepared statements from the
single collection was causing the long hangs. Here,
we've moved up to btm 2.1.3 and set the prepared
statement cache to 10 by default. (Note: for some
DBs this will require more active connections)
Merge pull request #1266 from sbesson/rebased/dev_4_4/11036_hql_pipeoutput

Do not enter interactive mode if hql command output is piped (rebased onto dev_4_4)
Review RawDataAcess example
Review DeleteData training example
Review ConnectToOMERO training example

- Add switch group example
Review ROIs training example
Do not flush all thumbnails when refreshing.

The flush will only happen before the thumbnail is updated
and when the browser is discarded.
merge dev_4_4 -D org -I include -E exclude: PR 982 (Add support for Ice 3.5)
merge dev_4_4 -D org -I include -E exclude: PR 988 (webgallery prototype from github/will-moore/webgallery)
merge dev_4_4 -D org -I include -E exclude: PR 1126 (Fix long-missing DELETE EventLogs)
merge dev_4_4 -D org -I include -E exclude: PR 1176 (Import status tb dev 4 4)
merge dev_4_4 -D org -I include -E exclude: PR 1233 (OMERO.matlab: add object creation functions (see #10637))
merge dev_4_4 -D org -I include -E exclude: PR 1234 (Web image object id extension 11022)
merge dev_4_4 -D org -I include -E exclude: PR 1249 (Dataset creation 11048)
merge dev_4_4 -D org -I include -E exclude: PR 1261 (11074 export close (rebased onto dev_4_4))