Canvas-grab

- Add "module_with_file" organize mode (module mode with unmoduled files). In this mode, canvas_grab will organize files in their corresponding module folder, and then download files not in module to "unmoduled" folder.
- Reduced release package size.
- Stability improvement for macOS prebuilt binary.

- You can now specify module folder name by template. For example, `{IDX} {NAME}`.
- You may enable `CONSOLIDATE_MODULE_SPACE` option to remove redundant consecutive space in module name. e.g. `Module 1` will become `Module 1`.
- You may set download mode on a per-course basis, with `COURSE_FOLDER.ORGANIZE_BY` config.
- Please refer to `config.example.toml` for how to enable these features.
- For new users, we provide a better set up process. Now canvas_grab will let you re-enter your API_KEY if you provided a wrong one.

- Add `NEVER_OVERWRITE_FILE` and `NEVER_DOWNLOAD_AGAIN` options in config to provide fine-grain control of what to download.
- Files that exist locally but lose sync with Canvas will be listed.
- Improved download and checkpoint. Now we'll create a temporary file for them in case of power failure and force majeure during download.
- Fix typo of `IGNORED_CANVAS_ID` in config. If you've changed this option before, be sure to update your config.
- [dev] Now we'll tell that "you're using development version" instead of always reporting there's more recent release.

- Now modules will be numbered in order shown on Canvas

- Support download by module
- If files in a course can't be downloaded by listing files, it will automatically fallback to download-by-module mode.

In this version, we fixed a bug in synchronizing course with no file available.
If you do not encounter this issue, you may choose NOT to upgrade.

- handle "Resource does not exist" course
- show course canvas ID in command-line