Update travis, Readme and remove .coveragerc

You can also get the occassion to expand README text including OCA word in the title (something like `OCA account payment modules for OpenERP`), and put the disclaimer in the footer:
```
----

OCA, or the Odoo Community Association, is a nonprofit organization whose 
mission is to support the collaborative development of Odoo features and 
promote its widespread use.

http://odoo-community.org/
```