Revert "Merge branch 'refactor/generic-metrics'"

This reverts commit a7f55b1714a51f767550e3210051035464acb1c2, reversing
changes made to c45f28d534c8788c7a62eb9fae320393d1c8d2eb.
Bring gauge and set tests up to spec
Update Changes
Add pargraph breaks to Changes
Release v0.31

  * BUG FIX: 0.30 would send sampled timers using an incorrect format.