[Zope-CMF] [dev] CMFSetup: purge mode and collision handling

[yuppie]

Hi!


Working on add-on support for CMFSetup, I have to modify some parts of 
it. Please let me know if the following changes break any relevant use 
cases.


1.) purge mode
--------------

The 'skip purge' mode already implements an update behavior as required 
by add-ons. Are there any scenarios where we want to run the same 
profile sometimes in purge mode and sometimes not? I don't think so.

So I'd like to remove the "Purge existing setup?" checkbox on the 
'Import' tab and modify related API methods.

Instead of that, the registerProfile method would take a new argument 
'profile_type'. If this type is BASE (the default value), should_purge 
is set to True. If it is EXTENSION, should_purge is set to False.


2.) collision handling
----------------------

Duplicate registry settings are currently interpreted as collisions and 
raise an error.

To support add-ons, I'd like to overwrite existing settings instead.


Cheers,

	Yuppie