* Update intstructions for existing nvim setups
If you already had a nvim setup, then this makes it so that the kickstarter can work without a problem. Having that file exist and loaded with plugins gives the script many issues.
Also better to have it be a shell command rather than have the script delete a bunch of files on your computer.
Use links to tagged releases rather than hardcoding 0.x and having to change it every few months. Fix markdownlint errors and some spelling, like using the official 'Neovim', not 'neovim'.
