Piwik installable for odoo 9

[dansanti]

Tested and available for use on odoo 9

[hbrunn]

👍 travis error unrelated

[elicoidal]

@dansanti Thanks for your contribution to the OCA.
Can you take the opportunity of the migration to update the module on the following:

• Please follow the guidelines from:
  https://github.com/OCA/maintainer-tools/blob/master/CONTRIBUTING.md
• Please follow the OCA README template:
  https://github.com/OCA/maintainer-tools/blob/master/template/module/README.rst
• We recommend to include a screenshot as well to help new comers (nice to have)
• Please use simple headers in all py files following OCA templates
  https://github.com/OCA/maintainer-tools/blob/master/template/module/__openerp__.py#L3

[simahawk]

@dansanti closing as it's on 9.0 and no action since more than 2 yrs.
Feel free to re-open it, thanks!