Bump src/collector

Bump cloudfoundry/collector:
  John Tuley:
     [#66065824] Listen for both "bad_requests" and "rejected_requests" from router ( Travis Success: https://travis-ci.org/cloudfoundry/collector/builds/19192300 )

Signed-off-by: John Tuley <jtuley@pivotallabs.com>
Merge pull request #294 from cloudfoundry/66065824-fix-collector-bad-requests

Bump src/collector for #66065824