This allows scripts to declare when they have finished their loading,
so we can now also know when wireplumber is done loading and ready to
handle clients
Related to !313
The load functions used to do 3 things:
- push the sandbox function on the stack
- load the file and push it as a function on the stack
- call the sandbox (or the file)
Now there are separate functions to do these 3:
- wplua_push_sandbox
- wplua_load_*
- wplua_pcall