[nvim]: add a keybinding and fix for vim.

.config/nvim/init.vim

@@ -11,3 +11,4 @@ require'lspconfig'.julials.setup{
     end
 }
 EOF
+:nmap K :lua vim.lsp.buf.hover() <CR>

.vimrc

@@ -17,7 +17,9 @@ call plug#begin('~/.vim/plugged')
 
     Plug 'tpope/vim-commentary'
 
-    Plug 'neovim/nvim-lspconfig'
+    if has('nvim')
+        Plug 'neovim/nvim-lspconfig'
+    end
 
 call plug#end()