[IMP] accounting documentation (#482)

* [REM] accounting: remove intro page

* [IMP] accounting: update documentation about cash rounding

accounting/overview/main_concepts.rst

@@ -5,6 +5,5 @@ Main Concepts
 .. toctree::
    :titlesonly:
 
-   main_concepts/intro
    main_concepts/in_odoo
    main_concepts/memento

accounting/overview/main_concepts/intro.rst

@@ -1,41 +0,0 @@
-===============================
-Introduction to Odoo Accounting
-===============================
-
-.. youtube:: 6XgKPjgyoec
-    :align: right
-    :width: 700
-    :height: 394
-
-Transcript
-==========
-
-Odoo is beautiful accounting software designed for the needs of the 21st century. 
-
-Odoo connects directly to your bank or paypal account. Transactions are synchronized
-every hour and reconciliation is blazing fast. It's like magic.
-
-Instantly create invoices and send them with just a click. No need to print them. 
-
-Odoo can send them for you by email or regular mail.
-
-Your customers pay online, meaning you get your money right away.
-
-Odoo accounting is connected with all Odoo our apps such as sale, purchase,
-inventory and subscriptions. 
-
-This way, recording vendor bills is also super quick. Set a vendor, select the purchase
-order and Odoo fills in everything for you automatically.
-
-Then, just use the SEPA protocol or print checks to pay vendors
-in batches.
-
-It's that easy with Odoo.
-
-Wait, there is more. You will love the Odoo reports. From legal statements to 
-executive summaries, they are fast and dynamic. Use Odoo's business intelligence feature to navigate
-through all your companies data.
-
-Of course, Odoo is mobile too. You can use it to check your accounts on the go.
-
-Try Odoo now, and join 2 million happy users.