Removed hdf5 from makefile, not needed right now
Can now switch between draw modes, still old per-pixel code though
Fixed button positions
Added 3 sample buffers for pixel-wise display, for min and max as well as mean per pixel.
This should make it possible to draw better spikes even when they're lost due to display sub-sampling
Implemented basic per-pixel voltage range display
Tiny lfpdisplay tweaks

increased draw range
Added simple pause function to lfpDisplay

Occasionally waits for a whole screen buffer cycle after resuming before
displaying again, possibly a full redraw issue. Generally seems to work
though.