Fix importprivkey on fidelity bond wallets

Previously importing a private key would result in a crash

jmclient/jmclient/cryptoengine.py

@@ -440,5 +440,6 @@ ENGINES = {
     TYPE_P2WPKH: BTC_P2WPKH,
     TYPE_TIMELOCK_P2WSH: BTC_Timelocked_P2WSH,
     TYPE_WATCHONLY_TIMELOCK_P2WSH: BTC_Watchonly_Timelocked_P2WSH,
-    TYPE_WATCHONLY_P2WPKH: BTC_Watchonly_P2WPKH
+    TYPE_WATCHONLY_P2WPKH: BTC_Watchonly_P2WPKH,
+    TYPE_SEGWIT_WALLET_FIDELITY_BONDS: BTC_P2WPKH
 }

jmclient/jmclient/wallet_utils.py

@@ -246,7 +246,8 @@ class WalletViewAccount(WalletViewBase):
         self.account_name = account_name
         self.xpub = xpub
         if branches:
-            assert len(branches) in [2, 3, 4] #3 if imported keys, 4 if fidelity bonds
+            assert len(branches) in [2, 3, 4, 5] #3 if imported keys, 4 if fidelity bonds
+                #5 if all those plus imported
             assert all([isinstance(x, WalletViewBranch) for x in branches])
         self.branches = branches