Create a `Development` page

[vy]

As agreed in the site structure document, create a "Development" page such that

• Outline:
  • Source repository
    • Branching scheme
  • Build instructions (replace references to BUILDING.adoc, BUILDING.md, etc.)
  • Release instructions
  • Contributing
    • Branching scheme
    • Changelog
• Remove BUILDING.adoc, BUILDING.md, etc.
• Remove javastyle.adoc
• Incorporate guidelines.adoc (some content might need to get moved to logging-site)
• Target 2.x, port to main