[WIP] Remove dialyzer supervisor

[axelson]

Fixes #101

I don't see why ElixirLS.LanguageServer.Dialyzer should have a supervisor, but all the other GenServers do not. They should all be treated the same.

I'm not completely sold on this approach. Instead it would probably be better to have a solid supervision hierarchy instead of relying on client to restart the server. For VSCode that happens automatically, but for other clients it does not, and we lose state that the server is relying on (such as the currently open files)

I'm curious about people's thoughts about a supervision hierarchy for ElixirLS

[lukaszsamson]

IIRC the supervisor was introduced to stop crashes in ‘:dialyzer’ calls bringing down the whole server.

[lukaszsamson]

2 years later I'm still not convinced, let's close this