Cleanup google and facebook login and cookie management

First,  cleanup `testERPSecurity`, moving related tests in sub-classes instead of big classes with lots of tests (diff is big, because methods are moved around)

Change google and facebook login to reuse `portal.setAuthCookie`, which is the central point to set a cookie securely so that it can be used for authentication.

Refactor management of oauth keys to fix [#20181121-1A36AE2](https://nexedi.erp5.net/bug_module/20181121-1A36AE2).

Some minor fixes in business template definition.

/reviewed-on nexedi/erp5!803