Update README for new CLI

Updated README instructions for new CLI commands.

Fixes #46 (closed)

src/rc_gpfs/cli/convert_to_parquet.py

@@ -95,7 +95,7 @@ def submit_batch(**kwargs):
 def convert_to_parquet() -> None:
     args = parse_args()
     if args['output_dir'] is None:
-        args['output_dir'] = args['input'].parent.parent.joinpath('parquet')
+        args['output_dir'] = args['input'].parent.joinpath('parquet')
     
     args['output_dir'].mkdir(exist_ok = True, mode = 0o2770)