Usage of an input-function in the FMU-layer of a Chain is not possible, yet

[juguma]

Please provide an example (and presumably missing functionality) to include an input-function into the FMU-layer of an FMIFlux.Chain. This is crucial when you work with FMUs that only create reasonable output with nonzero input.

Remark:

1. I know there are several options to define an input-function to an FMU: inputFunction!(t::T, u::AbstractArray{<:T}) inputFunction!(comp::FMU2Component, t::T, u::AbstractArray{<:T}) inputFunction!(comp::FMU2Component, x::Union{AbstractArray{<:T,1}, Nothing}, u::AbstractArray{<:T}) inputFunction!(x::Union{AbstractArray{<:T,1}, Nothing}, t::T, u::AbstractArray{<:T}) inputFunction!(comp::FMU2Component, x::Union{AbstractArray{<:T,1}, Nothing}, t::T, u::AbstractArray{<:T}) However I am not sure, if support of the more complex function types (i.e. those which do not only depend on t) are actually relevant for many users. I would be happy, if a purely time-dependent input function was supported.

2. When extending functionality, please keep in mind that in batched training one might want to use different inputs on different batches. (..as we discussed for the batch-wise parameters. This might be worth a second ticket, once this one is finished).