docs: few more additions and fixes for the sbroad part

See merge request picodata/picodata/docs!84

docs: tweaks and fixes for Mkdocs and code blocks

See merge request picodata/picodata/docs!83

docs: update sql queries section

See merge request picodata/picodata/docs!82

docs: update site structure and navigation

See merge request picodata/picodata/docs!81

docs: update Sbroad manual with eBNF diagrams

See merge request picodata/picodata/docs!80

docs: update Sbroad manual

See merge request picodata/picodata/docs!79

add architecture description

See merge request picodata/picodata/docs!78

more updates for PDF docs

See merge request picodata/picodata/docs!77

update PDF docs

See merge request picodata/picodata/docs!76

Docs

See merge request picodata/picodata/docs!75

doc: pull changes from the upstream clustering.md

See merge request picodata/picodata/docs!74

docs: platform image fix

See merge request picodata/picodata/docs!73

docs: fix typo in platform image

See merge request picodata/picodata/docs!72

docs: update description.md

See merge request picodata/picodata/docs!71

docs: changed Alt Workstation to Alt Server

See merge request picodata/picodata/docs!70

docs: add support for RED OS in install.md

See merge request picodata/picodata/docs!69

docs: fix spotted minor issues

See merge request picodata/picodata/docs!68

docs: provide discovery.md for reference

See merge request picodata/picodata/docs!67

docs: review and update deploy.md

See merge request picodata/picodata/docs!66

docs update PDF manuals, fix minor bugs

See merge request picodata/picodata/docs!65