Fix email sending.
Fix email sending.

  * Make sure the email has the To and From field filled correctly.

Change-Id: I1d706dcb3c3101f22fba55194399bf1580ce6be2

joyxu/kernelci-backend,joyxu/kernelci-backend,joyxu/kernelci-backend,kernelci/kernelci-backend,kernelci/kernelci-backend