Added auth_api: CMS_AUTHENTICATION_API, and for now moved registration instructions inside.

Added authentication module webapi, to provide registration via webapi.
Improved the roles display by providing table of permissions if asked.
Added various links in primary tabs to navigate back to roles or users, depending on the page.
Added datetime to-from string converters in CMS_ENCODERS.
Start removing CMS_ADMINISTRABLE.
Added permission to use simple core access token.
Added webapi for users: list, new, register.

modules/admin/handler/user/cms_admin_user_form_response.e

@@ -516,6 +516,7 @@ feature -- Form
 						create u.make (l_username)
 						u.set_email (l_email.as_string_8)
 						u.set_password (new_random_password (u))
+						u.mark_active
 						api.user_api.new_user (u)
 						if api.user_api.has_error then
 							-- handle error

modules/admin/handler/user/cms_admin_user_view_response.e

@@ -61,12 +61,18 @@ feature -- Execution
 			lnk.set_weight (2)
 			a_response.add_to_primary_tabs (lnk)
 
+
 			if a_user /= Void and then a_user.id > 0 then
 				lnk := api.administration_link (a_response.translation ("Delete", Void), "user/" + a_user.id.out  + "/delete")
 				lnk.set_weight (3)
 				a_response.add_to_primary_tabs (lnk)
 			end
 
+			lnk := api.administration_link (a_response.translation ("<< Users", Void), "users")
+			lnk.set_weight (10)
+			a_response.add_to_primary_tabs (lnk)
+
+
 				-- FIXME: [04/aug/2015] use a CMS_FORM rather than hardcoded html.
 				-- So that other module may easily integrate them-selves to add information.
 			create s.make_empty