Adds documentation for the EQL `substring` function.
Supporting changes:
* Creates a new "EQL function reference" page
* Updates the title of the "EQL syntax reference" page for consistency
* Adds a brief "Functions" section to the EQL syntax docs
* Updates EQL limitations docs to state that only array functions are
unsupported
I plan to add additional sections to this page with future PRs:
* Specify timestamp and event type fields
* Specify a join key field
* Filter using query DSL
* Paginate a large response
See #51057.
Adds documentation for basic EQL syntax.
Joins, sequences, and other syntax to be added as its supported
in future development.
Co-Authored-By: Ross Wolf <31489089+rw-access@users.noreply.github.com>
* Creates a top-level page for EQL in the ES reference.
This page contains a high-level introduction and will include a nav for other EQL docs pages as they're built.
* Creates a requirements page.
This page outlines the fields needed to use EQL in ES.
James Rodewig