- Removed unnecessary column from `SpamLog`
- Moved creation of SpamLogs out of its own service and into SpamCheckService
- Simplified code in SpamCheckService.
- Moved move spam related code into Spammable concern
- New concern `AkismetSubmittable` to allow issues and other `Spammable` models to be submitted to Akismet.
- New model `UserAgentDetail` to store information needed for Akismet.
- Services needed for their creation and tests.
gfyoung