Merge branch 'release-0.67.0' into develop

* release-0.67.0:
  Bumping version to 0.67.0
  Update several service models
Added resign ability to retries
Merge pull request #365 from kyleknap/resign-retry

Added resign ability to retries
Add back response headers to debug log

Also added an integration test to ensure we don't remove
this feature in the future.
Merge branch 'response-headers' into develop

* response-headers:
  Add back response headers to debug log
Bumping version to 0.68.0
Merge branch 'release-0.68.0'

* release-0.68.0:
  Bumping version to 0.68.0
  Add back response headers to debug log
  Added resign ability to retries