* 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>
This adds tests, supported types, and a signature image for `to_string`
and `to_version`. It also fixes the resolution of functions who's names
contain an `_`
Finally, it updates the docs for `ceil` to render the image more nicely.
Adds an `mv_join` function that joins together multivalue string fields.
You can combine this with out fancy new `to_string` to join together any
multivalued fields into a string.
