Romanucci & Blandin LLC merged with Baizer Kolar Neiman P.C., a 41-year-old boutique personal-injury firm based in Highland Park. The merger is effective today.Romanucci & Blandin gains three attorneys — Robert S. Baizer, Joseph E. Kolar and David A. Neiman — bringing its total headcount to 17.Baizer said the merger is a result of discussions with Romanucci & Blandin that started last fall.“It’s such an exciting opportunity for all of us in my firm to be able to expand our …