Function paddedKeyNamer

A padded key naming function.

Names keys like foo-000, foo-100, etc.

Note the number depends on the limit and the number of steps passed. The number is rounded to the nearest integer.

e.g. 10 steps with a limit of 1000: [foo-000, foo-100, ... foo-900]

Note that the last key will be foo-900 NOT foo-1000.

To make it end at foo-1000 use paddedKeyNamer((stepCount + 1) * desiredPadAmount).