ar-vinyeard compiles and runs:
- ar-function-kernel uses int for sign rather than bool in sign_at
- switched to dealing with a single functions themselves in value_at
- order of thresholds is handled correctly in ar-vineyard (max is the last one)
Write an audit for the data structure.
-DBOOST_UBLAS_TYPE_CHECK=0 is necessary since otherwise Boost's uBLAS gives a compile-time error
when it doesn't find sqrt for polynomials. It doesn't actually need it (e.g., for LU-decomposition,
but it looks for it during type check). (File a bug report with Boost?)