title: html5 canvas: auto font size for drawn wrapped rotated text
body: <p>suppose that there is a text to be drawn inside a rotated bounding rectangle (not aligned to normal axes x-y), and that <strong>text can be also rotated</strong>, 
  given the <em>max width</em> of the bounding box, how to select the <strong>best font size</strong> to use to draw a <strong>wrapped text inside</strong> that bounding box in html5 canvas and javascript?</p>
  
  <p>I know that method: <strong>measureText</strong>() can measure dimensions of give font size, but I need the inverse of that: using a known width to get the problem font size.</p>
  
  <p>thanks</p>