KOHIMA, July 22- The Nagaland unit of the Nationalist Congress Party (NCP) was formally constituted on Wednesday with former Assembly Speaker KV Keditsu as president and former Congress leader K Zhimomi as general secretary. The state executive committee of the NCP was formed after the first meeting, Zhimomi, who is spokesman of the state unit, said. The meeting resolved to field candidates in the region in the ensuing Lok Sabha elections.