Notify version: v1.0.3

Current Behavior:

custom_webook_url is typo'd

Expected Behavior: it should be custom_webhook_url

Steps To Reproduce:

put custom_webhook_url in a configuration file, try notify, you will receive this error Post "": unsupported protocol scheme ""

Anything else:

I would fix it myself but I'm in a hurry, remember to update the tests too!