network: testnet should use testnet

src/networks.js

@@ -54,7 +54,7 @@ var networks = {
     wif: 0xef,
     dustThreshold: 546,
     feePerKb: 10000,
-    estimateFee: estimateFee('bitcoin')
+    estimateFee: estimateFee('testnet')
   }
 }
 
@@ -65,10 +65,10 @@ function estimateFee(type) {
     var byteSize = tx.toBuffer().length
 
     var fee = baseFee * Math.ceil(byteSize / 1000)
-    if(network.dustSoftThreshold == undefined) return fee
+    if (network.dustSoftThreshold == undefined) return fee
 
     tx.outs.forEach(function(e){
-      if(e.value < network.dustSoftThreshold) {
+      if (e.value < network.dustSoftThreshold) {
         fee += baseFee
       }
     })