Support `MOI.ScalarNonlinearFunction`

[pulsipher]

It would be great for Alpine to support the new MOI nonlinear interface. This will be required for InfiniteOpt to use it.

[harshangrjn]

Agreed! @odow @blegat

[pulsipher]

The update to BARON.jl might be a helpful guide: jump-dev/BARON.jl#63

[odow]

There's a short-term "we could probably make it work fix" and then a longer rewrite to exploit the new structure. This is on my TODO list, but no ETA