lindapamg

Because I want to gain biconnected_components with edges to remove some unwanted edges. So , How can we solve this problem（error)?

> The error is [here](https://github.com/JuliaGraphs/LightGraphs.jl/blob/2a644c2b15b444e7f32f73021ec276aa9fc8ba30/src/biconnectivity/biconnect.jl#L53) : the edge is added only if `state.low[v] > state.depth[w]`, whereas it should be always added to the stack. I can make a PR, but...