Create a custom exception class for missing linter dependencies

Summary: I feel that we are abusing ArcanistUsageException. Throw a more tailed exception instead. Depends on D11197.

Test Plan: arc lint, I guess.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: avivey, Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D11205