A PageAlignedArray is an array which is guaranteed to have its memory be
page-aligned. Two convenient aliases are provided: PageAlignedVector{T} = PageAlignedArray{T,1}
and PageAlignedMatrix{T} = PageAlignedArray{T,2}.
These arrays should not be preferred in ordinary circumstances. However, some streaming DMA (direct memory access) peripherals may require a block of memory to be allocated on a page boundary, and therefore having an array in Julia that satisfies this requirement can be useful.