Add IntegralArrays.jl to dependencies

[abhro]

The following line https://github.com/JuliaImages/ImageFeatures.jl/blob/1d2e4e9760fcedcc0fc2fff043e97ddbc2c0e474/src/brisk.jl#L83 uses the IntegralArray() type, (from the IntegralArrays.jl package if I understand correctly) but the package is neither imported nor referenced in the dependencies. On its own, if create_descriptor() is called, it raises an UndefVarError, where `IntegralArray` not defined in `ImageFeatures`