Request: `-e ENDPOINT -h` should be the same as `-ep ENDPOINT`

Hyunwoo Kim requested that if a user runs something like:

```shell
ferry-cli -e getUserInfo -h
```

This should be equivalent to

```shell
ferry-cli -ep getUserInfo
```

Basically, `-h` given to a subparser should mirror a standard help flag, with `-h/--help` both working in this case.