DOC: Clarify IPv4 address / mask notation rules

Adds some examples regarding shorthand IPv4 address notation which might
be confused with RFC 4632 CIDR notation, leading to different than
expected results.
(cherry picked from commit eba5634f2c6d0eced75aacd28a5ae5e5d0613911)
(cherry picked from commit ed241d181d096fe1e1c709cc9addb5d981527ee0)
1 file changed