add copilot.vim plugin

vim/vimfiles/vimrc

@@ -11,6 +11,8 @@ filetype indent plugin on
 " Plugins {{{
 call plug#begin()
 
+Plug 'github/copilot.vim'      " do: Copilot setup
+
 Plug 'OmniSharp/omnisharp-vim' " After :PlugInstall do :OmnisharpInstall
 
 Plug 'dense-analysis/ale'