AbstractWrappedEnvironment

[colinxs]

It'd be nice if we had something like:

struct MyWrappedEnvironment{E<:AbstractEnvironment} <: AbstractWrappedEnvironment
    parent::E
end
# default definition somewhere in Lyceum
Base.parent(env::AbstractWrappedEnvironment) = env.parent
getobservation!(o, env::AbstractWrappedEnvironment) = getobservation!(o, parent(env))
# user-defined overload
getstate!(s, env::MyWrappedEnvironment) = # ...

So that you didn't have to copy out the entire environment just to tweak one little thing. As a motivating example, say one wanted to learn a dynamics model for an AbstractMuJoCoEnvironment. The inclusion of qacc_warmstart as part of state makes that difficult, and removing it requires copying out an environment. AbstractWrappedEnvironment is one way to deal with that.