* Corrected en files

* Split system-tables.md into separate files

* Fixed links.

* Fixed links.

* Fixed links.

* Fixed links.

* Add ref to original article

* Fixed links

* Add toc_folder_title and translate

* Add stack_trace.md, correct toc-title

* Fixed links

* Hypothesis testing

* Hypothesis testing

* Update run.sh, thanks @azat
Co-authored-by: NAnna Devyatova <annadevyatova@yandex-team.ru>
Co-authored-by: NSergei Shtykov <bayonet@yandex-team.ru>
Co-authored-by: Nalexey-milovidov <milovidov@yandex-team.ru>

* prefer relative links from root

* wip

* split aggregate function reference

* split system tables