Currency model admin now supports import / export

InvenTree/common/admin.py

@@ -1,9 +1,14 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
 from django.contrib import admin
 
+from import_export.admin import ImportExportModelAdmin
+
 from .models import Currency
 
 
-class CurrencyAdmin(admin.ModelAdmin):
+class CurrencyAdmin(ImportExportModelAdmin):
     list_display = ('symbol', 'suffix', 'description', 'value', 'base')