
ability to get wave data from guile
	(wavevar-value x) - return value at x-coord.

survey existing guile primitives and add new ones to fill out a useful set
for scripting in general, not just what the GUI offers at the moment.

custom measurements

Y zoom methods:
	manual: type in min and max for panel
	automatic-global: what we do now
	automatic-window: alway show min, max in current window zoom extents
	oneshot-global: compute min,max when clicked, not continually.
	oneshot-window: 

plotting quick-fix
	make log-scale work in plots

overhaul plotting
	move mostly into scheme
	keep "wave data export" function in C
	dialog box for options

documentation
	docstring extraction from guile
	get reference-manual auto-generation working
	write some introductory text to hold the auto-generated parts together

example guile scripts for useful functions

draw a real graticule in wave panels

move to top, move to bottom to select drawing order for visiblewaves in panel

"envelope" drawing algorithm (that doesn't alias when too many
datapoints for current zoom) 
Add an indication that there may be too many points on screen (simply
look at number of ivar points vs. number of pixels)

additional drawing styles
	linestyles - dashed, etc.
	symbols showing actual datapoints






