rename transfer to purchase

src/app/bc-info/purchase-history/purchase-history.component.html

@@ -1,10 +1,10 @@
 <div id="tx-history">
     <purchase 
         class="card"
-        *ngFor="let transfer of lastPurchases; index as i"
-        [hash]="transfer.hash"
-        [amount]="transfer.amount"
-        [extent]="transfer.extent"
-        [timestamp]="transfer.timestamp"
+        *ngFor="let purchase of lastPurchases; index as i"
+        [hash]="purchase.hash"
+        [amount]="purchase.amount"
+        [extent]="purchase.extent"
+        [timestamp]="purchase.timestamp"
     ></purchase>
 </div>