remove unused imports

stages/splitmerge.py

@@ -1,19 +1,15 @@
 import os
 import shutil
-import json
-import yaml
 from opendm import log
 from opendm.osfm import OSFMContext, get_submodel_argv, get_submodel_paths, get_all_submodel_paths
 from opendm import types
 from opendm import io
 from opendm import system
 from opendm import orthophoto
-from opendm.gcp import GCPFile
-from opendm.dem import pdal, utils
+from opendm.dem import utils
 from opendm.dem.merge import euclidean_merge_dems
 from opensfm.large import metadataset
 from opendm.cropper import Cropper
-from opendm.concurrency import get_max_memory
 from opendm.remote import LocalRemoteExecutor
 from opendm.shots import merge_geojson_shots, merge_cameras
 from opendm import point_cloud