Switch testing framework from MAIN to new UNITTEST network

UNITTEST inherites from MAIN but allows synamically changing its parameters using the ModifiableParams() interface

src/chainparamsbase.cpp

@@ -57,6 +57,20 @@ public:
 };
 static CBaseRegTestParams regTestParams;
 
+//
+// Unit test
+//
+class CBaseUnitTestParams : public CBaseMainParams
+{
+public:
+    CBaseUnitTestParams()
+    {
+        networkID = CBaseChainParams::UNITTEST;
+        strDataDir = "unittest";
+    }
+};
+static CBaseUnitTestParams unitTestParams;
+
 static CBaseChainParams* pCurrentBaseParams = 0;
 
 const CBaseChainParams& BaseParams()
@@ -77,6 +91,9 @@ void SelectBaseParams(CBaseChainParams::Network network)
     case CBaseChainParams::REGTEST:
         pCurrentBaseParams = &regTestParams;
         break;
+    case CBaseChainParams::UNITTEST:
+        pCurrentBaseParams = &unitTestParams;
+        break;
     default:
         assert(false && "Unimplemented network");
         return;