synopsis_generator.lua updated, mostly

list_file_extensions.lua

@@ -0,0 +1,19 @@
+#!/usr/bin/env luajit
+
+package.path = (arg[0]:match("@?(.*/)") or arg[0]:match("@?(.*\\)")) .. "lib" .. package.config:sub(1, 1) .. "?.lua;" .. package.path
+local utility = require "utility"
+local json = utility.require("dkjson")
+
+local search_path = arg[1]
+
+local file_extensions = {}
+utility.tree(search_path, function(file_path)
+  local _, _, extension = utility.split_path_components(file_path)
+  if extension then
+    file_extensions[extension] = true
+  end
+end)
+
+for extension in pairs(file_extensions) do
+  print(extension)
+end