* Move build instructions to contributing
* Add python pillow install instructions for win
* update linux instructions
* make cleaner menus
* Add macos help
* Update formatting and instructions in CONTRIBUTING.md
* Add build instructions reference to README
Added a note to refer to CONTRIBUTING.md for build instructions.
* Update build instructions in README.md
Clarified build instructions in README for different platforms.
* Fix step number in build instructions
Updated the step number in the build instructions to reflect the correct sequence.