mempool: replace size with vsize in getmempoolentry

Author: fanquake

Sources/CoreRPC/MemPool.swift

@@ -24,9 +24,9 @@ public extension CoreRPC {
         let fees: Fees
         let height: Int
         let modifiedfee: Double
-        let size: Int
         let spentby: [String]
         let time: Int
+        let vsize: Int
         let wtxid: String
     }