Add a CLI flag to support a timeout about ecspresso

[fujiwara]

@johncblandii ecspresso v2 adds --timeout cli flag. try it!

[fujiwara]

A configuration file of ecspresso is parsed as a template.
So you can set timeout by the TIMEOUT environment variable like the following example.

# ecspresso.yml
timeout: '{{ env `TIMEOUT` `10m` }}'

[johncblandii]

In CI, we call init, jq some task def changes, then call deploy. We don't have yq installed to edit the config.

This is why a default way would be better instead of us doing manual changes to configs in an automated scenario.

[fujiwara]

ecspresso supposes a typical use case as below,

1. Run ecspresso init manually. Create configuration/definition files.
2. Modify these files to templates manually and commit to a CI repository.
3. CI checkouts these files and runs ecspresso deploy with environment variables (defined by runtime).

I did not assume to modify definition files by jq or other tools.

I added typical use case into readme. #600

[fujiwara]

@johncblandii ecspresso's configuration file includes various elements (that are fixed by the environment, or are flexible by runtime).

This situation is confusing, but adding the --timeout flag makes more confusion.

So, I tried to omit the timeout element in a configuration file created by ecspresso init command at #602.

This fix became ecspresso init does not write timeout. Therefore you can add any timeout: "xxx" to the configuration file.

How about #602?

[johncblandii]

I'm fine with it being omitted, but let us supply one so we can control it in our CI/CD process without having to manipulate a file.

This is a very common CLI request. Just give us control over settings.