Neovim: add LSP signature and change cmp setting

.config/nvim/lua/plugins.lua

@@ -57,6 +57,12 @@ require('packer').startup(function()
 		after = 'vim-vsnip'
 	}
 
+	-- lsp signature
+	use {
+		'ray-x/lsp_signature.nvim',
+		config = function() require('plugins.lspsignature') end
+	}
+
 	-- autopairs
 	use {
 		'windwp/nvim-autopairs',