Fixed - Merging now resets layer opacities and names

UX - When using additive mode you need to use the full capture and re-plot (this is shown more obviously when plotting)

LUTs - You can now Import a custom LUT (4096 x 4096 based - Full LUT included for download) using ALT+L when in a pixel mode, to clear it and go back to built in LUTs press SHIFT+ALT+L when in a pixel mode.

C64 forced Browns/Blues - the last 2 LUTs (slider all the way to the right for colour palettes)

Other minor bugfixes to do with plot updating.