[TEST] guarantee REST tests execution order

REST tests are being shuffled before their execution. To guarantee their repeatability given the seed, their order needs to be always the same before the shuffling happens.

Closes #8745
[Doc] Add an UpdateRequest example to Java API doc

Closes #7083.

(cherry picked from commit f37355a)
[Doc] Java API: add search templates

Closes #7321.

(cherry picked from commit ee108e5)
[Doc] Java API: add information on JBoss EAP

Closes #3445.

(cherry picked from commit 26a0976)
Typo in error message with too few points for geo polygon filter.

Closes #8767
Docs: Added a command to start elasticsearch on bootup on Debian.

Close #8600
Docs: Add instructions to start elasticsearch on bootup on RHEL/Fedora.
[TESTS] Use a _default_ template to load field data lazily

Previously it was possible for the field data clearing in this test to
take too long, causing the test to time out.

This also switches to using `scaledRandomIntBetween` for the number of
fields.
[TESTS] Log what the _default_ template is in ElasticsearchIntegrationTest
[TEST] wait unitl all machines joined the cluster
Docs: add randomizedtesting-runner to testing-framework.asciidoc

Close #8450
[ALLOCATION] Speed-up disk-threshold decider

Instead of iterating all shards of all indices to get all relocating
shards for a given node we can just use the RoutingNode#shardsWithState
method and fetch all INITIALIZING / RELOCATING shards and check if they
are relocating. This operation is much faster and uses pre-build
data-structures.

Relates to #6372