change neovim config structure

remove dial.nvim
add grubbox.nvim

roles/neovim/files/lua/plugins.lua

@@ -0,0 +1,7 @@
+return require('packer').startup(function()
+	--- Packer can manage itself
+	use 'wbthomason/packer.nvim'
+
+	-- Colorscheme
+	use 'gruvbox-community/gruvbox'
+end)