Broken readme links

[SimonBiggs]

Just flagging that there are a range of broken links within the README:

• anthropic-retrieval-demo/README.md

  Line 140 in a032154

  It is straightforward to add new SearchTools to the demo as well by creating a new Python file for the tool in the [/searcher/searchtools/](searcher/searchtools) folder.

• anthropic-retrieval-demo/README.md

  Lines 244 to 245 in a032154

  	[You can see this example in the examples/ folder here using local vectorstores.](examples/local-retrieval.ipynb)
  	[You can see this example in the examples/ folder here using remote vectorstores.](examples/remote-retrieval.ipynb)

Also the following colab link isn't publicly accessible:

• anthropic-retrieval-demo/README.md

  Line 207 in a032154

  [Examples of all the search integrations are in this Colab.](https://colab.research.google.com/drive/1WStiEn60TSKHnEfiLn2Vtgg9BPE-bV9t#scrollTo=2NhRHuWIVSTg)

Thanks for the report @sjswerdloff (feel free to add others that I've missed)