Fixed a sphinx error: Inline literal start-string without end-string.
`` `` is not allowed.
Kea supports the following formats when specifying hexadecimal data:
- ``Delimited octets`` - one or more octets separated by either colons or
- spaces (``:`` or `` ``). While each octet may contain one or two digits,
+ spaces (":" or " "). While each octet may contain one or two digits,
we strongly recommend always using two digits. Valid examples are
"ab:cd:ef" and "ab cd ef".