Adding cashier closing feature  (#15273)

* adding cashier closing feature

cashier closing feature has been added as now the cashier can make a
closure to record every thing from his pos as the expenses which has
been paid and the custody which he had at the starting and the amount
which is in his save and the system will record the date and time and
the user and the total net amount automatically which supposed be equal
to all of his sales invoices totals

* add cashier closing link at pos menu

* add cashier closing link to accounts config file

adding cashier closing link at accounts config file to show it at the
accounts module page

* adding more features to cashier closing

adding from time to the cashier closing in case the cashier working more
than one shift also giving him the ability to add the type of payments
to his cashier closure ,
also adding validation to be sure the from time is less than to time.

* Update cashier_closing.py
diff --git a/erpnext/config/accounts.py b/erpnext/config/accounts.py
index 5526ac8..660f78c 100644
--- a/erpnext/config/accounts.py
+++ b/erpnext/config/accounts.py
@@ -34,6 +34,11 @@
 				},
 				{
 					"type": "doctype",
+					"name": "Cashier Closing",
+					"description": _("Cashier Closing")
+				},
+				{
+					"type": "doctype",
 					"name": "Auto Repeat",
 					"label": _("Auto Repeat"),
 					"description": _("To make recurring documents")