Sevenbridges-python

Improvements:
- Retry policies are revised and unified
- Default timeout for uploads and downloads is raised to 300s
- Default part_size for uploads has been set to 32Mb

Bugfixes:
- When passed, download chunk_size will now be accurately calculated
- Fixed randomly failing upload tests

Improvements:
- Secondary files task output avoid lazy fetching

Preload file names from CWL 1 task outputs.
Preload file type from task outputs.

Improvements:
- Retry error handlers

Improvements:
- Retry strategy after connection failure

Improvements:
Add `autorename` flag to `submit_import` call.
Add `autorename` and `preserve_folder_structure` flags to bulk submit of imports calls.
Fix the doc-strings.