Updated the API with the legend 'reverse' option.

API.md

@@ -164,7 +164,7 @@ legend: {
     backgroundColor: null or color
     backgroundOpacity: number between 0 and 1
     container: null or jQuery object/DOM element/jQuery expression
-    sorted: null/false, true, "ascending", "descending" or a comparator
+    sorted: null/false, true, "ascending", "descending", "reverse", or a comparator
 }
 ```
 
@@ -197,9 +197,10 @@ specify "container" as a jQuery object/expression to put the legend
 table into. The "position" and "margin" etc. options will then be
 ignored. Note that Flot will overwrite the contents of the container.
 
-Legend entries appear in the same order as their series by default. To
-sort them alphabetically, you can specify "sorted" as tue, "ascending"
-or "descending", where true and "ascending" are equivalent.
+Legend entries appear in the same order as their series by default. If "sorted"
+is "reverse" then they appear in the opposite order from their series. To sort
+them alphabetically, you can specify true, "ascending" or "descending", where
+true and "ascending" are equivalent.
 
 You can also provide your own comparator function that accepts two
 objects with "label" and "color" properties, and returns zero if they