Alter backoff logic (low exponential with jitter).
Alter backoff logic (low exponential with jitter).

 * Backoff now starts at 8192 us.
 * Each failure increases backoff *= 17/16.
 * Each sleep has random jitter in the range [-4192,4192) us.

Laeeth/fq,circonus-labs/fq,circonus-labs/fq,circonus-labs/fq,circonus-labs/fq,circonus-labs/fq,Laeeth/fq,Laeeth/fq,Laeeth/fq,circonus-labs/fq