Update README with QNX8 aarch64, RPi showcase guide, and existing docs improvements#246

Subramanian-K812 wants to merge 8 commits into

eclipse-score:maineclipse-score/reference_integration:mainfrom

qorix-group:Subramanian-K812_readme_refreshqorix-group/reference_integration:Subramanian-K812_readme_refreshCopy head branch name to clipboard