Merge pull request usablica#259 from waynn/master

fixes usablica#194 by changing the CSS class for "Done" so it's not the same as ...

Author: afshinm

intro.js

@@ -1040,6 +1040,7 @@
       skipTooltipButton.innerHTML = this._options.skipLabel;
     } else if (this._introItems.length - 1 == this._currentStep || this._introItems.length == 1) {
       skipTooltipButton.innerHTML = this._options.doneLabel;
+      skipTooltipButton.className = 'introjs-button introjs-donebutton';
       prevTooltipButton.className = 'introjs-button introjs-prevbutton';
 
       if (this._options.hideNext == true) {