Approximating body measurements from standard size data

[joelle-o-world]

This PR adds some data from Winnifred Owen and combines it with scipy interpolation to approximate all the body measurements (when using BodyMeasuremnt class) based on the measurements provided.

This is probably transphobic, because the data is based on cis women. However thats the point. As most of my clients are trans, I should be able to learn through use how this data should be adjusted/enhanced in order to get a more inclusive model of the human body.

• An xy line graph class for interpolating sizes
• Approximate some measurements using straight lines
• Copy sizing table from Winnifred Owen book
• Use an actual dictionary for size table
• Interpolate womens sizes
• Convert measurements to mm
• Fix sizing interpolation
• Smart body measurement approximation