--- Address: renamed isIPv6() to getType()
+++ Address: added static getTypeName(AddressType) function
BIG REFACTORING: routing tables and routes now implement a common IRoutingTable and IRoute (details below)

Motivation: allow uniform access to the IPv4, IPv6 and possibly other routing tables;
e.g. some wireless networks may use MAC address as network address. Also, in
simulation it sometimes makes sense to work with simple abstract addresses like
module names, indices or IDs.

Being able to uniformly access routing tables containing different types of
addresses makes it possible to implement routing protocols in generic way.
I.e. the same DYMO module can work with IPv6, IPv6, MAC and other addresses
without change and recompiling.

Ingredients of this patch:
- generic Address class that can hold all kinds of addresses (=union)
- interfaces for generic access: IRoutingTable, IRoute, INetworkDatagram, etc.
- Ping refactoring (use generic addressing instead of hardcoded IPv4+IPv6)
- merged routing table change notification constants for IPv4 and IPv6
--- fixed the lost changes after moved IPv6Route to a new file
----NodeBase fixed: remove routingFile parameter
module tests: fixed routingFile parameters
----fixed RoutingTableRecorder for Omnetpp master, too
----SCTP fixes: was unspecified address problems

the new Address class can store more different unspecified addresses
the sctp code creates different unspecified addresses
IPv4: implemented netfilter, ported MANET protocols to use it

- IPv4.cc/h no longer has #ifdef WITH_MANET
- INetfilter added, good for all network layer protocols
InternetCloud: refactoring for ARP and INetFilter

connections between ARP and IPv4 was changed, IPv4 now not send all msg to ARP.
delayer registered as a netfilter hook to IPv4
----InternetCloud: fingerprint changed
InternetCloud: ChangeLog
Turn off IPv6 routing by default.
introducing routingTableModuleName parameter -- TODO half-cooked!

- attempt is to get rid of the *Access classes, this time only for routing tables
- parameter name should rather be routingTableModule
- problem is e.g. IPv4AddressConfigurer -- how should it know where to find routing tables of hosts??
----routingTableModuleName parameter setting was missed in NodeBase6
Address: new address types: MACAddress, ModuleIdAddress, ModulePathAddress; added GenericNetworkProtocol & co.
---- GenericNetworkProtocol: bugfix: nextHop vs nexthop, *iter was erased before used the iter->nextHop
Address: Implemented efficient address.

Also:
- Added check to prevent accidentally turning an IPv6 address into something else.
- Added check for NONE address type in conversion functions.
- Added some inline declarations.
--- Address: str() was duplicated
added MultiNetworkLayer