[BUG] fromdate parameter not recoginzed

[lamerjack]

if i write this command:
C:\prg\hitrava>Hitrava.py --tar com.huawei.health.tar --from_date 20190820

i get this error

usage: Hitrava.py [-h] [-z ZIP] [-j JSON] [--json_export] [-f FILE] [-s {Walk,Run,Cycle,Swim_Pool,Swim_Open_Water}]
[-t TAR] [--from_date FROM_DATE] [--pool_length POOL_LENGTH] [--tcx_insert_altitude_data]
[--output_dir OUTPUT_DIR] [--use_original_filename] [--output_file_prefix OUTPUT_FILE_PREFIX]
[--suppress_output_file_sequence] [--validate_xml] [--log_level {INFO,DEBUG}]
Hitrava.py: error: argument --from_date: Invalid date or date format (expected YYYY-MM-DD): '20190820'.

[lamerjack]

Works fine with
C:\prg\hitrava>Hitrava.py --tar com.huawei.health.tar --from_date 2019-08-20
is just wrong the readme (where i found the example)