Fix/rand interval

[mo8it]

If at least one of the two endpoints are excluded from an interval, the rand function should not choose it.

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Why the Union with Array{<:Interval}? I did remove it because it is similar with the functionality in Base:

julia> rand([ClosedInterval(i, i + 1) for i in 1:10])
7..8

julia> @which rand(fill(ClosedInterval(1.0, 2.0), (2,2)))
rand(X) in Random at /usr/share/julia/stdlib/v1.7/Random/src/Random.jl:259

julia> using ReinforcementLearning

julia> rand([ClosedInterval(i, i + 1) for i in 1:10])
5..6

julia> @which rand(fill(ClosedInterval(1.0, 2.0), (2,2)))
rand(s::Union{Array{<:Interval}, Interval}) in ReinforcementLearningEnvironments at /home/mo/.julia/packages/ReinforcementLearningEnvironments/UhI2A/src/base.jl:9

What was the intention of it? I guess, the intention is to get a random action from each interval, not a random interval. This was not working. If this functionality is needed, I can add a commit for it.

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Also, I did add two methods to choose one of the endpoints if it is not an open interval. This has better performance than rand, but does not restrict to using IntervalSets, because we always have a fallback to rand.

[mo8it]

The first commit is old, sorry. But it is merged anyway.

[findmyway]

What was the intention of it? I guess, the intention is to get a random action from each interval, not a random interval. This was not working. If this functionality is needed, I can add a commit for it.

You guessed it. Since we now have Space as the container, we don't need that function any more.

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Could you resolve the conflict first? So that we can get this merged into the master branch.

[mo8it]

Is it fine now?