cli: add `waymond help` sub-command

[scriptnull]

Right now running waymond without any arguments is looking like this.

$ ./waymond    
error loading config: open waymond.toml: no such file or directory

There is no way to understand what are all the commands and flags supported by waymond. So, we will add a new sub-command called help.

$ waymond help
waymond - Autoscale Anything Anywhere All at once!

help - prints help

-config [PATH]  file path of waymond configuration (.toml)