Only pure PAS plugin parts are implemented.

By understanding external_login in ERP5UserManager it is not required to repeat
authenticateCredentials logic.

Thanks to this ERP5ExternalAuthenticationPlugin can be used only as credential
extraction plugin.

Extend test suite to prove that enabling ERP5ExternalAuthenticationPlugin does
not impact default scenario.

It is possible to configure external authentication plugin to use REMOTE_USER
variable.

Thanks to this no need of code duplication is required, and
ERP5ExternalAuthenticationPlugin can be responsible for only one thing:
extraction of credentials passed by external service.

Activation of additional plugin shall not impact another tests.

Follow the specification of shacache and shadir: PUT is used in shadir,
POST is used in shacache in order to create new content. erp5_web can be used
without any modification to serve fully restfull POST interface.

Create special action for Web Site which reacts on POST type of request and
support it by low level functionality. This action is available in web view
only and affects only Web Sites configured for shacache.

Other changes:

 * do not check uploaded content, just return calculated sha
 * break compatibility during upload (better now then later)
 * avoid hiding errors during publishing content by hiding exceptions in
   WebSite_publishDocumentByActivity
 * do randomisation in tests and make them live test safe
 * connect to running web server in tests in order to use all stacks during
   uploading and downloading content
 * cleanup erp5_web_shacache and erp5_web_shadir business templates and remove
   not needed scripts
 * during testing treat running site as blackbox and do not try to be too smart

events (i.e. Mail Message) in CRM event_module.
Typo & XXX: comment added.

Messages) are to be stored inside CRM event_module.

Use absolute path, and display useful log when sql dump is not found

Recovery | Update

by human interaction.