* Document MATCH and QUERY function predicates.
* Polish the functions pages and add a list of functions to the main Functions & Operators page.
(cherry picked from commit 4cec0ae1b962ec7ea011a290aec72740386eb808)
To avoid having to specify each spec by hand (which can miss specs to be
added), the test infrastructure now performs classpath discovery so that
each spec added, is automatically considered.
Relates #40358
(cherry picked from commit d0f60b4425c731509aa8ca765d55f563f866ef90)
* Added Limitations page
* Made the aggregations page follow the common template for functions
* Modified all tables to have the first row's cells content centered
* Polishing in other various sections
Split function section into multiple chapters
Add String functions
Add (small) section on Conversion/Cast functions
Add missing aggregation functions
Enable documentation testing (was disabled by accident). While at it,
fix failing tests
Improve spec tests to allow multi-line queries (useful for docs)
Add ability to ignore a spec test (name should end with -Ignore)
James Rodewig
Andrei Stefan
Costin Leau
Marios Trivyzas
Costin Leau