toot 0.40.0

This release includes a rather extensive change to use the Click library
(https://click.palletsprojects.com/) for creating the command line
interface. This allows for some new features like nested commands,
setting parameters via environment variables, and shell completion.
Backward compatibility should be mostly preserved, except for cases
noted below. Please report any issues.

 * BREAKING: Remove deprecated `--disable-https` option for `login` and
   `login_cli`, pass the base URL instead
 * BREAKING: Options `--debug` and `--color` must be specified after
   `toot` but before the command
 * BREAKING: Option `--quiet` has been removed. Redirect output instead.
 * Add passing parameters via environment variables, see:
   https://toot.bezdomni.net/environment_variables.html
 * Add shell completion, see:
   https://toot.bezdomni.net/shell_completion.html
 * Add `tags info`, `tags featured`, `tags feature`, and `tags unfeature`
   commands
 * Add `tags followed`, `tags follow`, and `tags unfollow` sub-commands,
   deprecate `tags_followed`, `tags_follow`, and `tags tags_unfollow`
 * Add `lists accounts`, `lists add`, `lists create`, `lists delete`,
   `lists list`, `lists remove` subcommands, deprecate `lists`,
   `lists_accounts`, `lists_add`, `lists_create`, `lists_delete`,
   `lists_remove` commands.
 * Add `--json` option to tags and lists commands
 * Add `toot --width` option for setting your prefered terminal width
 * Add `--media-viewer` and `--colors` options to `toot tui`. These were
   previously accessible only via settings.
 * TUI: Fix issue where UI did not render until first input (thanks Urwid
   devs)