* Configuration is now handled in this order:
--config flag
ZELLIJ_CONFIG_FILE env
get_default_config_dir() (directories-next)
HOME/.config/zellij (for mac convenience)
SYSTEM_DEFAULT_CONFIG_DIR (for distributions to specify sensible
defaults ontop of zellij)
from assets
* Fix default.yaml file
* Move default.yaml file to assets directory
This changes the `config` subcommand to a config flag.
Add option subcommand for now, for the clearing of default path.
Add `ZELLIJ_CONFIG` environment variable.
The configuration locations are now as follows:
* `--config` flag
* `ZELLIJ_CONFIG` environment variable
* default config location
in that order.
