Specialize Base.to_index for AnyCuArray{Bool}

[pabloferz]

Fixes #106 and fixes #131. It is not he most performant solution as discussed in #131.

Probably a better solution would be to revert this Base.to_index specialization, check if there are LogicalIndexes among the results of to_indicices in setindex!(::CuArray, ...), and have a specialized kernel for _setindex! and LogicalIndex in GPUArrays.jl, but I guess that can be improved later.

@maleadt

[maleadt]

Sounds good for now, thanks! Maybe add a # TODO comment in the code with some details though?

[pabloferz]

Done. (it seems that putting [skip ci] in the commit message didn't work, you might want to cancel that redundant build)

[maleadt]

Yeah I've had it happen as well, despite https://buildkite.com/docs/pipelines/ignoring-a-commithttps://buildkite.com/docs/pipelines/ignoring-a-commit ...