Simple BASH script for POSTing to the Slack API with custom messages.
env SLACK_URL=<your_slack_url> ./post_slack --title "<message_title>" --body "<message_body>"
-t | --title: Message title.
-b | --body: Message body.
-c | --color: Message color. Color options are: good warning danger error. (optional)
-u | --url: Slack URL to send the POST. Overrides env SLACK_URL variable. (optional)
-h | --help: Print a help message. (optional)