Add minimum oracle fee

src/Neo.SmartContract.Framework/Services/Neo/Oracle.cs

@@ -5,6 +5,7 @@ namespace Neo.SmartContract.Framework.Services.Neo
     [Contract("0x3c05b488bf4cf699d0631bf80190896ebbf38c3b")]
     public class Oracle
     {
+        public const uint MinimumResponseFee = 0_10000000;
         public static extern string Name { get; }
         public static extern void Request(string url, string filter, string callback, object userData, long gasForResponse);
     }

tests/Neo.Compiler.MSIL.UnitTests/TestClasses/Contract_NativeContracts.cs

@@ -23,6 +23,11 @@ public static string OracleName()
             return Oracle.Name;
         }
 
+        public static uint OracleMinimumResponseFee()
+        {
+            return Oracle.MinimumResponseFee;
+        }
+
         public static string DesignationName()
         {
             return Designation.Name;

tests/Neo.Compiler.MSIL.UnitTests/UnitTest_NativeContracts.cs

@@ -55,6 +55,18 @@ public void Test_Oracle()
             var entry = result.Pop();
 
             Assert.AreEqual("Oracle", entry.GetString());
+
+            // Minimum Response Fee
+
+            testengine.Reset();
+            result = testengine.ExecuteTestCaseStandard("oracleMinimumResponseFee");
+
+            Assert.AreEqual(VMState.HALT, testengine.State);
+            Assert.AreEqual(1, result.Count);
+
+            entry = result.Pop();
+
+            Assert.AreEqual(0_10000000u, entry.GetInteger());
         }
 
         [TestMethod]