Automatic selection of vertical axis in 1D plots #612
Description
Since #593 it is possible to make 1D plots with the coordinate on the y-axis and cube data on the x-axis. It is proposed that when a call to a 1D plotting function is made in the form:
plot(cube)
and when the cube's dimension coordinate is a vertical coordinate, the plot should automatically have the coordinate on the y-axis.
The rationale for this is that iris should always try and produce the most sensible plot when given no specific instructions about coordinates.