added neorg plugin

lua/holger/plugins/neorg.lua

@@ -0,0 +1,22 @@
+return {
+	"nvim-neorg/neorg",
+	lazy = false, -- load immediately
+	version = "*", -- latest stable release
+	dependencies = { "nvim-lua/plenary.nvim" }, -- Neorg requires plenary
+	config = function()
+		require("neorg").setup({
+			load = {
+				["core.defaults"] = {}, -- default modules
+				["core.concealer"] = {}, -- enable the concealer
+				["core.dirman"] = { -- workspace management
+					config = {
+						workspaces = {
+							notes = "~/notes",
+						},
+						default_workspace = "notes",
+					},
+				},
+			},
+		})
+	end,
+}