title: gnuplot rotate axis label (xlabel, ylabel and zlabel) not working in 3d plots
body: <p>I am having hard time aligning y-axis and z-axis labels with axis tics on my 3d plots. 
  Here is my code.</p>
  
  <pre><code>  set ylabel "Infectious Duration (days)" rotate by 90
    set zlabel "Compute Time (sec)" rotate by 90
    set logscale x
  
    splot  "TCompISIS3d.txt" using 1:2:3 title 'SIS-Inf1' with points , \
           "TCompISIS3d.txt" using 1:4:5 title 'SIS-Inf4' with points , \
           "TCompISIS3d.txt" using 1:6:7 title 'SIS-Inf10' with points , \
           "TCompISIS3d.txt" using 1:8:9 title 'SIS-Inf50' with points
  </code></pre>
  
  <p>But it doesn't rotate any of the labels. Please Help!</p>