Refactor examples directory

[dominicprice]

At the moment this has a bunch of example dealer scripts; while these are useful it might be better if they were moved into a dealer subdirectory, and some Python scripts with examples of using the actual endplay library itself added to the directory. Examples of examples which might be nice to have include:

• Reading a PBN file and generating double dummy results from this
• A script which takes a bunch of results and calculates an imps score against a table which plays double dummy
• Something which scrapes a results website (e.g. bridgewebs) to get scores, then does some manipulations with them
• Generating deals using the Actions API, rather than relying on the run_script function