Add support for loading ~/.config/wezterm/local.lua config

wezterm.lua

@@ -82,4 +82,13 @@ for _, map in pairs({
   })
 end
 
+-- Attempt require(module) load a module, don't fail if its missing.
+-- Additionally, call the returned function passing in the wezterm and config
+-- objects defined in this file.
+local try_require = function(module)
+  pcall(function() require(module)(wezterm, config) end)
+end;
+
+try_require('local')
+
 return config