At a 30 fps rate with a limit on the number of window messages per
frame. This is somehow needed for Melda plugins, as they otherwise
dispatch tiemr messages indefinitely after opening a second editor with
seemingly no way around it.
With this and some refactoring #15 should be almost done.
This is a bit more restrictive than the old approach that only skipped
when `effEditOpen()` got called after `effEditGetRect()`. Not sure why
the Melda plugins block indefinitely on the message loop without this
now.
Based on a function. This is needed because the message loop should be
skipped while any of the plugins is opening their GUI, similar to how
`EditorOpening` worked for individually hosted plugins.
Handles for things like timers should be unique on a per-thread basis in
the Win32 API, but apparently window classes have to be unique for the
entire application.
This was not a problem with individually hosted plugins because the
entire process got terminated at once, but here we all threads to shut
down gracefully when a plugin's sockets get closed. I wish this wouldn't
need all these try-catches, but we're not writing Haskell here.
The only issue remaining is that for some reason only the first
instance's editor works, at least for Serum. This might be because of
the message loop.