Add l10n_ch_hr_payroll.

Swizerland Payroll Rules for Odoo.

Features list :
* Add Swiss salary rule categories
* Add Swiss salary rules
* Add children in school to employee
* Add LPP range to contract
I think basically all information should be in README. External links could be used for reference.
At least it should warn this link is french only ?

Thought I am concerned about having all module README linking to external pages. The user who search for modules will surely want more information when reading README and not being redirected to any other website.

Plus it would be tempting for every one to put a link to make some advertisement this could create a link war nightmare in each modules.

Nevertheless, I think it's ok to have additional link if the README itself provides enough info.
More opinions on this from community would be welcome.