Redirect to homepage if campaign not found
Use quiet_assets to remove asset output in logs
Move payment data sync above reward association

Reward association forces a save to generate the payment instance's ID,
which fires the after_create email notification with incorrect data when
a reward exists
Merge pull request #106 from Crowdtilt/quick-fix-redirect-and-email

Quick fixes to admin notification email after payment and redirect if campaign is not found