Docs: Fix curl statements in query-cache.asciidoc

Closes #7989
Docs: Update highlighting.asciidoc

Added note about how to highlight on the `_all` field

Closes #7991
Tweaking upgrade test to improve reliability.
Docs: cross_type query needs to be cross_fields

Closes #8021
Update cjk-bigram-tokenfilter.asciidoc
Docs: Removing escape character

The escape character `\` doesn't work and should be removed from the documentation.

Closes #8029
Snapshot/Restore: fix snapshot of a single closed index

Snapshot of a closed index can leave snapshot hanging in initializing state.

Fixes #8046
Docs: add the predefined language-specific stopword lists to stop-tokenfilter.asciidoc
Docs: adds note about using null_value with dynamic templates

Closes #7874
Docs: Fix order for PUT _mapping docs

Closes #8083
Docs: Added RethinkDB River to list of community plugins

Closes #8016
Docs: Update query-string-query.asciidoc

Update sample

Closes #8024
Docs: fix typo

Closes #8111
Docs: Typo: s/by/be/

Closes #8114
Improve amibiguous ES_HEAP_SIZE warning in deb init script

Closes #3554
Add debug logging to help diagnose intermittent upgrade test failures.

Also fixed indentation in ElasticsearchMergePolicy.
Remove unnecessary log level setting in upgrade test.
Docs: Documented the http.*host and transport.*host settings
Docs: Update id-field.asciidoc

It is strange to provide an example with `"store" : false` when talking about possibility of enabling the field to be stored.
Broke the line in the mapping in two lines for better readability.
More verbose sentence above the mapping.

Closes #7894
Docs: Some Data Cant't be obtained.

In previous case, the first 100 data can't be obtained.

Closes #8103