Clean & Separate PSNU and PSNU UIDS
split_psnu.RdThis function removes the contacanated data contained in the same cell. The psnu column in the Target Setting Tool contains both the psnu, psnuuid, and meta data on type - Country/SNU/DREAMS/Military. `split_psnu` breaks out psnu and psnuuid into two columns and removes any other extraneous information.