Merge pull request #848 from Xanewok/related-diagnostics

Support related diagnostics

Author: nrc

Cargo.lock

@@ -15,7 +15,7 @@ cargo_metadata = "0.5.2"
 env_logger = "0.5"
 failure = "0.1.1"
 jsonrpc-core = "8.0.1"
-languageserver-types = "0.39"
+languageserver-types = "0.40"
 lazy_static = "1"
 log = "0.4"
 racer = "2.0.12"