Allium: Add main net fork at 58671 (#41)

* Switch mainnet at block 58671

Author: ryan-shaw

src/chainparams.h

@@ -86,7 +86,9 @@ class CChainParams
     void UpdateVersionBitsParameters(Consensus::DeploymentPos d, int64_t nStartTime, int64_t nTimeout);
     int GetPoWAlgo(int nHeight) const {
         if (strNetworkID == CBaseChainParams::TESTNET && nHeight > 10){
-                return ALGO_ALLIUM ;
+            return ALGO_ALLIUM ;
+        } else if(strNetworkID == CBaseChainParams::MAIN && nHeight > 58670){ // Approx 19:00 2018-02-16 UTC
+            return ALGO_ALLIUM;
         } else {
             return ALGO_SCRYPT;
         }