Add PiecewisePolynomial, QuaternionFunctionofTime, and Serialize Pybindings

[AlexCarpenter46]

Proposed changes

Adds some pybindings necessary for creating volume data with functions of time in python.

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• The code is documented and the documentation renders correctly. Run
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Further comments

[knelli2]

You can squash everything in directly. No need for fixups

[knelli2]

You can just call this argument functions_of_time. The fact that it's shared is just a python thing, and they are clearly deserialized (since it's not a vector<char>)

[knelli2]

Just loop over all keys in the input map and call get_clone. No need to get specific names

[knelli2]

Just for organization, move these classes right after the FunctionsOfTime::FunctionOfTime class.

[knelli2]

For the PiecewisePolynomial, let's bind both order 2 and 3. To avoid duplicating code, write a lambda that's templated and call that for 2 and 3 like so

const auto bind_piecewise_polynomial = [&]<size_t Order>() {
  // code that you have now using Order
  // Have each name be "PiecewisePolynomial" + std::to_string(Order)
};

bind_piecewise_polynomial.template operator()<2>();
bind_piecewise_polynomial.template operator()<3>();

(no need to do this for the Quat)