Auto merge of #2797 - str4d:2493-active-merging, r=bitcartel

Implement z_mergetoaddress for combining UTXOs and notes

Closes #2493.

src/wallet/wallet.h

@@ -267,6 +267,7 @@ typedef std::map<JSOutPoint, CNoteData> mapNoteData_t;
 struct CNotePlaintextEntry
 {
     JSOutPoint jsop;
+    libzcash::PaymentAddress address;
     libzcash::NotePlaintext plaintext;
 };
 
@@ -1126,6 +1127,13 @@ public:
                           int minDepth=1,
                           bool ignoreSpent=true,
                           bool ignoreUnspendable=true);
+
+    /* Find notes filtered by payment addresses, min depth, ability to spend */
+    void GetFilteredNotes(std::vector<CNotePlaintextEntry>& outEntries,
+                          std::set<libzcash::PaymentAddress>& filterAddresses,
+                          int minDepth=1,
+                          bool ignoreSpent=true,
+                          bool ignoreUnspendable=true);
     
 };