[BlueOS] Update docs to match latest state (1.1 / 1.2)

[ES-Alexander]

Documents:

• Notify user if BlueOS has no access to the host computer BlueOS#1962
• core: frontend: NetworkSpeedTest: Remove network result status BlueOS#1978
• core: frontend: add autopilot restart button to power menu BlueOS#2062
• Index: update to 1.2
• Folder extensions BlueOS#2010
  • Partially documented in [BlueOS-devel] document extension creation process #147
• core: tools: mavp2p: Add first version BlueOS#2072
• core: services: kraken: Add size of extension BlueOS#2124
• core: services: log_zipper: Use gzip over zip BlueOS#2163
• core: frontend: extensions manager: try to ensure a minimal progressbar width, use better colors BlueOS#2215
• Allow choosing the MAVLink router BlueOS#2235
• core: tools: scripts: red-pill: Add option to select user BlueOS#2273
• core: allow disabling services using environment variables BlueOS#2293
• core: frontend: Change text from 'Enable Wizard' button BlueOS#2334
• core: frontend: components: version-chooser: Add restore button on remote repository BlueOS#2349
• log_zipper: Delete .gz files if available disk space is below limit BlueOS#2359
• Overview: what's new in 1.2?
  • Better extensions support (file browser, standard binding location, custom SVG icons)
  • Stability improvements:
    • MAVP2P option made available for routing
    • Automatic system log file compression and rotation
    • Bootstrap?
      • I can't remember if 1.2 is supposed to solve the factory reset issue, or if that was earlier, but we should probably be recommending people update
  • Improved developer options (custom user support in red-pill, environment-variable based service disabling)
  • Coming soon: easier vehicle setup and sensor calibrations

Not covering:

PR	Reason
bluerobotics/BlueOS#1916	Feature not working yet: bluerobotics/BlueOS#2548
bluerobotics/BlueOS#2333 bluerobotics/BlueOS#2342 bluerobotics/BlueOS#2368 bluerobotics/BlueOS#2375 bluerobotics/BlueOS#2453	Shhh - it's a secret! (for now)
bluerobotics/BlueOS#2183 bluerobotics/BlueOS#2031	Got removed before ending up in a stable release - will be added later as an extension
bluerobotics/BlueOS#2078	Covering in #147 instead

[ES-Alexander]

Preview of the main changes:
BlueOS-1.2-main-docs-changes.zip