plotyaxis

Adds a light grey y-axis to the plot, behind the data

plotyaxis adds a y-axis to the current axes

plotyaxis(AX) adds a y-axis to the axes defined by the handle AX

NOTE: plotyaxis should be called at the end of the plotting commands, or
at least after the y-limits of the axes have been specified.
Please leave a comment if you experience any issues/bugs or if you have any suggestions for improvements.

Enjoy!