Transmission-rpc

if you didn't see any `DeprecationWarning` when you are using 6.0.0, it's safe to upgrade to this version.

BREAKING CHANGES:

some deprecated properties and methods are removed:
- `client.locate_torrent_data`, use `client.move_torrent_data(move=False)` instread.
- `torrent.seedRatioLimit`, use `.seed_ratio_limit` instead.
- `torrent.seedRatioLimited`, use `.seed_ratio_limited` instead.
- `torrent.files`, use `torrent.get_files()` instead.
- `torrent.date_active`, use `torrent.activity_date` instread.
- `torrent.date_added`, use `torrent.added_date` instread.
- `torrent.date_started`, use `torrent.start_date` instread.
- `torrent.date_done`, use `torrent.done_date` instread.

Breaking Changes:

1. remove `PRIORITY`, `RATIO_LIMIT` `RatioLimit` and `IdleLimit`, use enum `Priority`, `RatioLimitMode` and `IdleMode` instead.
2. `File.priority` are now enum `Priority` instead of string.
3. `Torrent.priority` are now enum `Priority` instead of string.
4. `Torrent.seed_idle_mode` are now enum `IdleMode` instead of string.
5. `Torrent.seed_ratio_mode` are now enum `RatioLimitMode` instead of string.

Breaking Changes
* drop python 37 by trim21 in https://github.com/trim21/transmission-rpc/pull/326

Bug Fixes
* Make Status enum format to its str value by gazpachoking in https://github.com/trim21/transmission-rpc/pull/314

Features

* add `py.typed` marker file (306)