Currently, all the sizes in the VIO/VConnection and corresponding InkAPI are all 32-bit (int on x86_64).
Do we want to change these to 64-bit before 2.0 so as to minimize API changes for 2.X? Pros: - reduce interface changes going forward Cons: - actual large document support many require additional changes which we may not want to do for 2.0. - in practice large documents are unreasonably inefficient in 2.0
