* adding readme function overview image

* updated image

* fixing image alt text

* centering image?

* reduced image

* tweak image url for cache busting

* rename image to update

* chat chain logo image

* added logo image

* logo-32px

* don't commit graphic sources

* graphic updates

* fixed spelling

* cleanup the configuration README

* make chatgpt response tests more robust

Even when given specific instructions like "Return the response 'Hi'."
ChatGPT (and LLMs in general) don't always follow the
instructions *exactly* (for example, ChatGPT will often respond to the above
prompt with "Hi!").

As a result, equality testing on the response makes for flaky tests. This change
keeps the test prompts, but instead matches on the responses with `=~`. Still
not perfect, but less likely to be flaky, which in tests seems like a win.

* link to demo project

* add "update_custom_context" to LLMChain
- added tests

* add support for setting the `OpenAI-Organization` header in requests to the OpenAI API

* set pattern match in `DataExtractionChain` to look for `role: :assistant` as it appears to be the only valid result at this stage

* improved the data extraction prompt
- didn't consistently handle 'null' values

* update readme
- add example of openai_org_id config

* improve pattern match on data extraction chain

* update version

* updated changelog

* put "Elixir" in the Readme title

---------

Co-authored-by: Mark Ericksen <brainlid@gmail.com>
Co-authored-by: Ben Swift <ben@benswift.me>
Co-authored-by: Adam Mokan <amokan@gmail.com>