added checkpoints for KMD blockchain. need to be tested.

- added method SetCheckpointData for CChainParams.
- as we can't check asset it or not in CMainParams() constructor, because command line arguments don't initialized at that time, we will execute SetCheckpointData in chainparams_commandline later.

changes was tested in komodo-qt wallet, but additional tests wouldn't be superfluous.

src/chainparams.h

@@ -87,15 +87,18 @@ public:
     void SetRegTestCoinbaseMustBeProtected() { consensus.fCoinbaseMustBeProtected = true; }
 
     void SetDefaultPort(uint16_t port) { nDefaultPort = port; }
+    void SetCheckpointData(Checkpoints::CCheckpointData checkpointData);
+
     //void setnonce(uint32_t nonce) { memcpy(&genesis.nNonce,&nonce,sizeof(nonce)); }
     //void settimestamp(uint32_t timestamp) { genesis.nTime = timestamp; }
     //void setgenesis(CBlock &block) { genesis = block; }
     //void recalc_genesis(uint32_t nonce) { genesis = CreateGenesisBlock(ASSETCHAINS_TIMESTAMP, nonce, GENESIS_NBITS, 1, COIN); };
     int nDefaultPort = 0;
     CMessageHeader::MessageStartChars pchMessageStart; // jl777 moved
+    Consensus::Params consensus;
+
 protected:
     CChainParams() {}
-    Consensus::Params consensus; 
 
      //! Raw pub key bytes for the broadcast alert signing key.
     std::vector<unsigned char> vAlertPubKey;