[CR] RES-550-DisplayStatsOnWordPress

Now you are able to see SendGrid summary statistics in dashboard and more statistics in separate page.

- [x] Confirm that all dependencies for this PR are listed/linked below. Ex. db-schema change, ops dependency, or PR's in other repos
- [x] Confirm this PR is safe to merge and deploy at will. If not, please describe the conditions necessary for deployment. Update this when it is safe to deploy.