added options to sort() and _sort()
updated tests for sortingOptions
included descending option in private _sort
Merge branch 'sortingOptions' of github.com:rishabhm/yui3 into rishabhm-sortingOptions
Cleanup API docs and code comment for ModelList descending sort feature
Remove questionable uses of short-hand conditional function calls in ML
Add ModelList test to make sure `reset()` sorts when `silent: true`
Update Model List's docs and HISTORY for descending sort feature
Build Model List