Add point in nonconvex Polygon check

[mforets]

cc @mvanzulli

[David-davidlxl]

I wanted to see if there's any progress on this. I'm working with a nonconvex polygon and I'd really like to have the membership-check functionality.
For example, I'd like the following code to run without error:

using LazySets
polygon = Polygon([[0, 0],
    [2.1314, 0.9141],
    [1.8282, 1.2219],
    [0.9141, 0.9141],
    [0.6063, 1.5251],
    [-0.6063, 2.1360],
    ])
println([1, 1] ∈ polygon)

Update:
The code

using LazySets
polygon = VPolygon([[0, 0],
    [2.1314, 0.9141],
    [1.8282, 1.2219],
    [0.9141, 0.9141],
    [0.6063, 1.5251],
    [-0.6063, 2.1360],
    ], apply_convex_hull=false)
println([1, 1] ∈ polygon)

does appear to produce the correct result, even though it's inconsistent with plot(polygon) (#3127 (comment))

[schillic]

@David-davidlxl: I added an implementation in #3628. It will likely take some time until this gets reviewed and merged, so I suggest you check out the branch or copy the code.
Also, I tried to cover every edge case, but there might be one missing. So feel free to beta-test it :)

[David-davidlxl]

@schillic Thank you so much!
I copied your ∈(x::AbstractVector, P::Polygon) function and tested it with my polygon, and it seems to work perfectly! #3628