Dedupe Batch Merge

Also log hours at http://senatedev.senate.state.ny.us/issues/show/4535.

Keeping the scope limited for now, here is the spec as follows:

From "Find and Merge Duplicate Contacts" page (list of dupes), provide a link to a pop-up form for Batch Merge of all results with following options:

• 'Safe Mode' OR 'Aggressive Mode'

• If Aggressive - option to select (bias to) Older Data / Newer Data when conflict is detected. Plus a hook to implement other algorithms for choosing which contact to bias to when there's a conflict (to handle "gotchas").

• If Safe - merges with no chances of conflicts are performed. Preference is to add the records (no overwrites). Merges with conflicts are skipped.

A bin script to merge all or group N, safe vs aggressive mode, which works like UI batch merge above.