add backoff support to the `Repeater`, and leverage it in Entities. has nice side effect of speeding up many of the tests which rely on this repeater, including SoftwareProcessSubclassTest which goes from 10s total to 1s total.
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Merge pull request #1463 from ahgittin/repeater-backoff

add backoff support to the `Repeater`, and leverage it in Entities. has ...