Always return the same instance of ParameterCollection

This is done just replacing the data. We need that behavior
to make sure that updated data from atImport rules is visible
by all users of the data.

Conflicts:
	app/lib/models/CPS/RuleController.js
Add a cache for rules/dictionaryRules
new module CPS/elements/AtImportCollection

Conflicts:
	app/lib/models/CPS/parsing/atImportFactories.js