documentation

Pull request #1494: feature/DEV-2509-7.0-D. Added secure DB creation instructions for MySQL/MariaDB, PostgreSQL/TimescaleDB, Oracle; restructured "Best practices".

Merge in WEB/documentation from feature/DEV-2509-7.0-D to release/7.0

* commit '1018d063318a4f9d06359579b73ea817f574a8df': (25 commits)
  [DEV-2509] Fixed broken formatting
  [DEV-2509] Added line breaks for a better looking note
  [DEV-2509] Updated page numbering
  [DEV-2509] Refined security-related note
  [DEV-2509] Moved pages
  [DEV-2509] Removed linked instructions
  [DEV-2509] Refined wording
  [DEV-2509] Clarified default/easy vs. advanced instructions
  [DEV-2509] Clarified note
  [DEV-2509] Removed comment from code block
  [DEV-2509] Updated code block syntax
  [DEV-2509] Updated link
  [DEV-2509] Fixed link
  [DEV-2509] Removed italics from linked pages
  [DEV-2509] Added secure DB creation instructions for Oracle
  [DEV-2509] Added secure DB creation instructions for PostgreSQL/TimescaleDB
  [DEV-2509] Refined note & example
  [DEV-2509] Moved updated X-Frame-Options content (merge conflict resolution)
  [DEV-2509] Added note linking to best practices
  [DEV-2509] Updated secure DB creation instructions for MySQL/MariaDB
  ...