Add editor.gpuDisabled option to prevent React editor from using layers

When gpuDisabled is true, we use `translate` instead of `translate3d`
to position various elements, preventing the creation of GPU layers.
Rename editor option to useHardwareAcceleration
Pass useHardwareAcceleration property down to CursorComponent instances
:lipstick: method name
Merge pull request #2789 from atom/ns-react-disable-gpu-option

Add editor.gpuDisabled option to prevent React editor from using layers