llama-index-networks package (#11413)

* lint

* pants tailor

* remove unnecessary files/folders

* make api_key an optional field

* make secret field optional as well

* top level imports

* prerelease version bump

* remove misleading env variables

* override gitignore to add data to demo

* add note in demo README that you can use  instead of

* update demo contributor poetry.locks pyproject.toml

* published v0.1.0; updated demo deps