Some improvements around message display.#432

Merged

ehuss merged 2 commits intorust-lang:masterfrom ehuss:message-filtering

May 18, 2020

+101-59

Commits on May 12, 2020

Filter "warnings emitted" message.
ehuss
committed

Commits on May 18, 2020

Better handle diagnostics pointing outside of the workspace.
ehuss
committed