Since we're picking off the easy functions to implement that are matlab
core functions and not implemented in Octave, I looked at namelengthmax.
In matlab this is 63 which is basically limited by the string name
reserved for the variable name in matlab's "save" file format. However,
the same limits don't apply in Octave and the variable name length limit
is essentially "2^31-1". However when Octave writes to a mat-file it
truncates the variable names to 63 character (or 31 characters for v5
files).
So if we implement namelengthmax should we return 63, or 2^31-1? Is this
function of any use in any case?