[docs] minor opening stock added

docs/user/accounts/docs.user.accounts.opening_stock.md

@@ -0,0 +1,21 @@
+---
+{
+	"_label": "Opening Stock"
+}
+---
+
+
+You can upload your opening stock in the system using Stock Reconciliation. Stock Reconciliation will update your stock for a given Item on a given date for a given Warehouse to the given quantity.
+
+Stock Reconciliation will make a “difference entry” (the difference between the system stock and the actual stock in your file) for the Item.
+
+Tip: Stock Reconciliation can also be used to update the “value” of an Item.
+
+To make a Stock Reconciliation, go to:
+
+> Stock > Stock Reconciliation > New Stock Reconciliation
+
+and follow the steps mentioned on the page.
+
+![Stock Reconciliation](img/stock-reconciliation1.png)
+