Tiltmeter 0.4.0

Added

• tiltmeter init --from-har session.har writes the config from a HAR file exported from
  the browser's Network tab: one endpoint per JSON API the page called. Tokens, cookies,
  API keys and password fields become ${VAR} placeholders and are never written or
  printed. --host keeps one host and its subdomains; POST, PUT, PATCH and DELETE requests
  are left out unless you pass --include-writes (GraphQL queries count as reads).