Humblebundle-downloader

- Stop using md5 & sha1 hashes to check if file is unique (was creating duplicate downloads of the same file)
- Strip periods from end of directory & file names
- Rename older versions of a file before download the new one

- Delete failed downloaded files

- Filename saved is now the original name of the file
- key used in cache is different due to changing the file name
- _this may result in duplicate downloads if you have run the older version_
- Support for downloading a single Bundle/Purchase by using the
flag `-k` or `--key` and getting the key from the url of a purchase

- gen-cookies now works with SSO feature and 2FA logins
- Added `--include` & `--exclude` cli args to filter file types

- Replace `:` with `-` in filenames
- Ignore items that do not have a web url

- Started change log
- Added more detail to readme
- Removed the use of f-strings to support more python versions
- Fixed bug where folders and files were only a single letter