All server parameter of type CIDRRangeListParameter are using glue code in order to set and retrieve the value of the parameter. However, this glue code must be duplicated for all server parameter of that type. This was fine when there was one or two server parameter using this type, but now there's more of them.

1. Define the CIDRRangeListParameter class inheriting from ServerParameter and use this type instead of the generated glue code. This new type should be defined in cidr_range_list_parameter.h.
2. Remove IngressRequestRateLimiterExemptionList, MaxIncomingConnectionsOverrideServerParameter and MaxEstablishingConnectionsOverrideServerParameter in favor of this new type.
3. Make the functions appendCIDRRangeListParameter and setCIDRRangeListParameter private to cidr_range_list_parameter.cpp, in the anonymous namespace.