(wiki)(feat) Dollar char in the beginning of each line in code examples

Made every line in the code blocks to start with the dollar character as per the instructions from: - https://developers.google.com/style/code-syntax - https://make.wordpress.org/docs/style-guide/developer-content/command-line-syntax/ This is basically an opposite of https://github.com/klzgrad/naiveproxy/issues/794 Feel free to pull changes from my forked wiki: https://github.com/YuriySamorodov/naiveproxy.wiki.git Thank you in advance , Yuriy