keep input folder by default

sisyphus/global_settings.py

@@ -133,7 +133,7 @@ def file_caching(path):
 #: If the job internal work directory should be kept or deleted during clean up
 JOB_CLEANUP_KEEP_WORK = False
 #: If the job internal input directory with symlinks to input jobs should be kept or deleted during clean up
-JOB_CLEANUP_KEEP_INPUT = False
+JOB_CLEANUP_KEEP_INPUT = True
 #: Default value for job used by tk.cleaner to determine if a job should be removed or not
 JOB_DEFAULT_KEEP_VALUE = 50
 #: How many threads should update the graph in parallel, useful if the filesystem has a high latency