Cast-control

This release upgrades `PyChromecast` to version `7.7.2`.

You can install this version like so:
bash
python3 -m pip install chromecast_mpris==0.6.4

This version upgrades `mpris_server` and removes an unused dependency on `dbus-python`.

You can install this version like so:
bash
python3 -m pip install chromecast_mpris==0.6.3

Changes:
- Connect to device by supplying its UUID
- Allow users to supply `-r/--retry-wait` flag
- YouTube video opening and queuing
- Better error text
- Better help text
- Back-end refactoring

Installation:
bash
$ python3 -m pip install chromecast_mpris==0.6.1


v0.4.0-release
- Changed log level flag `-l/--log-level` to use the name of the log level as a string, instead of an `int`. Example: `chromecast_mpris -l debug`
- Added host flag `-h/--host`. Users can specify the hostname or IP address of the casting device they want to connect to.

- Upgrade PyChromecast to 7.5.1
- Refactored back end a bit, nothing that users will notice

This version upgrades PyChromecast to 7.5.0.