Round text coordinates consistently.

The core implementation used parseInt, which was originally to catch
text values, but really only stayed due to its side-effect of flooring
the values.  The canvas implementation has never rounded coordinates.
This led to various one-pixel rendering glitches between the two
implementations.  I've fixed the problem by consistently rounding
coordinates to the nearest whole number.

jquery.flot.canvas.js

@@ -140,7 +140,7 @@ browser, but needs to redraw with canvas text when exporting as an image.
 											y = Math.ceil(y - 2);
 										}
 
-										context.fillText(line.text, linex, y);
+										context.fillText(line.text, Math.round(linex), Math.round(y));
 										y += line.height;
 									}
 								}

jquery.flot.js

@@ -385,8 +385,8 @@ Licensed under the MIT license.
 		// Move the element to its final position within the container
 
 		info.element.css({
-			top: parseInt(y, 10),
-			left: parseInt(x, 10)
+			top: Math.round(y),
+			left: Math.round(x)
 		});
 	};