mtlb_axis Matlab axis emulation function

## Syntax

    mtlb_axis(X)
                mtlb_axis(st)
                mtlb_axis(axeshandle, ...)
                [mode,visibility,direction]=mtlb_axis('state')

## Arguments

X

  a vector of reals ([xmin xmax ymin ymax] or [xmin xmax ymin ymax zmin zmax])

st

  a string ('auto', 'manual', 'tight', 'ij', 'xy', 'equal', 'square', 'vis3d', 'off', 'on')

axeshandle

  handle of the current axes entity

## Description

Matlab `axis` have not a Scilab equivalent function.

The function `mtlb_axis(...)` is used by `mfile2sci` to replace `axis(...)` when it was not possible to know what were the inputs while porting Matlab code to Scilab. This function will determine the correct semantic at run time (axis `fill`, axis `image` and axis `normal` are not implemented). If you want to have a more efficient code it is possible to replace `mtlb_axis` call by `get(axeshandle, prop)` call (prop is an axis property, see axis_properties)

Caution: `mtlb_axis` has not to be used for hand coded functions.