better handling of s1ap ue context release request, better mscgen logs

openair-cn/MME_APP/mme_app_bearer.c

openair-cn/MME_APP/mme_app_context.c

openair-cn/MME_APP/mme_app_itti_messaging.h

openair-cn/MME_APP/mme_app_main.c

openair-cn/NAS/EURECOM-NAS/src/nas_proc.c

openair-cn/NAS/nas_itti_messaging.c

openair-cn/NAS/nas_itti_messaging.h

openair-cn/S1AP/s1ap_common.h

openair-cn/S1AP/s1ap_mme.c

openair-cn/S1AP/s1ap_mme_handlers.c

openair-cn/S1AP/s1ap_mme_handlers.h

openair-cn/S1AP/s1ap_mme_itti_messaging.c

openair-cn/S1AP/s1ap_mme_itti_messaging.h

openair-cn/S1AP/s1ap_mme_nas_procedures.c

openair-cn/S1AP/s1ap_mme_retransmission.c

openair-cn/SGW-LITE/sgw_lite_handlers.c

openair-cn/SGW-LITE/sgw_lite_task.c

openair-cn/SGW-LITE/spgw_config.c

targets/SCRIPTS/msc_gen.py