* Break out 'Limitations' into separate page
* Add REST API docs
* Restructure commands, functions, and operators refs
* Add placeholder for getting started guide
* Group 'Syntax', 'Metafields', and 'MV fields' under 'Language'
* Add placeholder for Kibana page
* Add link from landing page
* Apply uniform formatting to ACOS, CASE, and DATE_PARSE function refs
* Reword default LIMIT
* Add support for COUNT(*)
* Move 'Commands' and 'Functions and operators' to individual pages
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Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>
Describes how we fetch multivalued fields by default, return them as
json arrays, how the internal sort order is not guaranteed, how most
functions will turn them into null, and how some fields remove
duplicates on save.
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Co-authored-by: Abdon Pijpelink <abdon.pijpelink@elastic.co>