restore derivation strategy on txps

lib/model/txproposal.js

@@ -79,6 +79,7 @@ TxProposal.create = function(opts) {
   x.proposalSignaturePubKey = opts.proposalSignaturePubKey;
   x.proposalSignaturePubKeySig = opts.proposalSignaturePubKeySig;
   x.addressType = opts.addressType || Constants.SCRIPT_TYPES.P2SH;
+  x.derivationStrategy = opts.derivationStrategy || Constants.DERIVATION_STRATEGIES.BIP45;
   x.customData = opts.customData;
 
   if (_.isFunction(TxProposal._create[x.type])) {
@@ -127,6 +128,7 @@ TxProposal.fromObj = function(obj) {
   x.proposalSignaturePubKey = obj.proposalSignaturePubKey;
   x.proposalSignaturePubKeySig = obj.proposalSignaturePubKeySig;
   x.addressType = obj.addressType || Constants.SCRIPT_TYPES.P2SH;
+  x.derivationStrategy = obj.derivationStrategy || Constants.DERIVATION_STRATEGIES.BIP45;
   x.customData = obj.customData;
 
   return x;

lib/server.js

@@ -1286,6 +1286,7 @@ WalletService.prototype.createTx = function(opts, cb) {
           walletN: wallet.n,
           excludeUnconfirmedUtxos: !!opts.excludeUnconfirmedUtxos,
           addressType: wallet.addressType,
+          derivationStrategy: wallet.derivationStrategy,
           customData: opts.customData,
         };