Update cat.nodes regex

Support for multi-word node names like 'Henry "Hank" McCoy'
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: Adding community-contributed Scout plugins

Scout plugins for reporting key node, cluster, and index health metrics.

Closes #7937
Docs: Fix order for PUT _mapping docs

Closes #8083