If the email is not already set during acceptation

erp5_free_subscription: Do not add Free Subscription Request to a user but can be added to a person with the same email

For Base_viewKnowledgePadMacroLibrary

Conflicts:
	product/ERP5Security/__init__.py

Conflicts:
	product/ERP5OOo/tests/testDms.py

Change Preference accessor to use category property. Build accessor from accessor holder accessors and not from properties.

Conflicts:
	product/ERP5Form/tests/testPreferences.py

bug #20160107-9E3B60