Assertion:
START attribute behavior for "0" and negative values:
OL list with START="5":
filler text
  1. LI item 1
  2. LI item 2
  3. LI item 3
filler text

OL list with START="0":
filler text
  1. LI item 1
  2. LI item 2
  3. LI item 3
filler text

OL list with START="-5":
filler text
  1. LI item 1
  2. LI item 2
  3. LI item 3
filler text