redefines ProtocolNumber as newtype around CInt (formerly type alias for CInt)
that re-derives all instance methods for CInt that are defined in Foreign.C.Types

defines and exports pattern synonyms for commonly used protocol-number constants (defined in "netinet/in.h")
(IPPROTO_(IP|IPV4|IPV6|TCP|UDP|ICMP|ICMPV6|RAW)) as well as UnsupportedProtocol and GeneralProtocol patterns

refactored function definitions previously relying on (ProtocolNumber ~ CInt) to use unwrapper function

implements bijective read/show instances for ProtocolNumber whose default behavior is to directly read and show integer values with no constructor syntax

Unbreaks doctest by substituting new `show` value of defaultProtocol
where it appears in haddock examples

Clarifies behavior of show for ProtocolNumber to highlight that
pattern synonym names and their corresponding show values are based
on assumption of IP protocol families even though the type itself
remains general over all protocol families.

Redefines ProtocolNumber synonyms in terms of canonical "magic" numbers
from IANA reference (https://www.iana.org/assignments/protocol-numbers)
rather than CPP-constants from C header file.

Removes UnsupportedProtocol as all definitions are unconditional instead
of relying on C header-file macro definitions; redefines test case to
ensure that the value 'ProtocolNumber (-1)' is represented shown as "-1"
rather than "UnsupportedProtocol"

Renames IPPROTO_IP (dummy for '0') as DefaultProtocol, both as a pattern
synonym and in read/show boilerplate bijection (as well as in haddock
examples and tests/Network/SocketSpec.hs)