Add notes field to purchase order line item

InvenTree/order/migrations/0010_purchaseorderlineitem_notes.py

@@ -0,0 +1,18 @@
+# Generated by Django 2.2.2 on 2019-06-13 11:54
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('order', '0009_auto_20190606_2133'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='purchaseorderlineitem',
+            name='notes',
+            field=models.CharField(blank=True, help_text='Line item notes', max_length=500),
+        ),
+    ]