Add init scripts as relevant paths to all directories.

This doesn't feel ideal. Though it's true that all directories are influenced by
any init scripts they have, the directory middleware shouldn't need to know
about Lua.

I don't really want to go back into working on the middleware chain since it
mostly feels like busywork when there are other things to build on in Rojo.

also all of this feels really complicated

src/snapshots/serve_session__change_script_meta_before.snap

@@ -13,6 +13,9 @@ metadata:
   relevant_paths:
     - /root
     - /root/init.meta.json
+    - /root/init.lua
+    - /root/init.server.lua
+    - /root/init.client.lua
 children:
   - id: id-2
     name: test