net: Providing an interface for mapLocalHost

Contributes to #564 by providing an interface for mapLocalHost
through net -> node interface -> clientModel. Later this value can be
read by GUI to show the local addresses.

src/interfaces/node.h

@@ -168,6 +168,9 @@ public:
     //! Get num blocks.
     virtual int getNumBlocks() = 0;
 
+    //! Get network local addresses.
+    virtual std::map<CNetAddr, LocalServiceInfo> getNetLocalAddresses() = 0;
+
     //! Get best block hash.
     virtual uint256 getBestBlockHash() = 0;