PLT-530 - MarketDataEnvironment, part 2

This PR adds overrides to two of the curve building classes in analytics to expose a more modern API. The original method parameters include arrays, concrete map types and maps with array values. The new methods use ``List``, ``Map`` and ``Multimap``.

Check with @marc-opengamma, but I don't think there is any reason for these to be LinkedHashMaps. If this is correct then we can remove the copying here. I would argue that this is as good an opportunity we're going to get to make the change