An international qualitative study exploring patients’ experiences of cutaneous leishmaniasis: study set-up and protocol by Erber, AC, Arana, B, Bennis, I, Salah, A, Boukthir, A, Noriega, MDM, Cissé, M, Cota, GF, Handjani, F, Kebede, MG, Lang, T, Carvajal, L, Marsh, K, Medina, D, Plugge, E, Olliaro, P