Allow creating Filters for data clean-up/tagging rules

[punchagan]

Allow creating filters like Email filters to apply categories/tags, change remarks, etc as rules. They could either be in the DB or just in the config, for easier editing?

Run the filters automatically when importing new data.

Allow running filters over specific subsets of the data?

Once we have a nice model for defining these filters, it would be nice to also allow easily recording actions in the UI and simplifying the creation of filters ala quickFilters for Thunderbird.