add placement auto for tooltips + tests… kinda sad about this doe

dist/js/bootstrap.js

@@ -1180,6 +1180,10 @@
         this.options.placement.call(this, $tip[0], this.$element[0]) :
         this.options.placement
 
+      var autoToken = /\s?auto?\s?/i
+      var autoPlace = autoToken.test(placement)
+      if (autoPlace) placement = placement.replace(autoToken, '') || 'top'
+
       $tip
         .detach()
         .css({ top: 0, left: 0, display: 'block' })
@@ -1192,6 +1196,26 @@
       var actualWidth  = $tip[0].offsetWidth
       var actualHeight = $tip[0].offsetHeight
 
+      if (autoPlace) {
+        var $parent = this.$element.parent()
+
+        var orgPlacement = placement
+        var docScroll    = document.documentElement.scrollTop || document.body.scrollTop
+        var parentWidth  = this.options.container == 'body' ? window.innerWidth  : $parent.outerWidth()
+        var parentHeight = this.options.container == 'body' ? window.innerHeight : $parent.outerHeight()
+        var parentLeft   = this.options.container == 'body' ? 0 : $parent.offset().left
+
+        placement = placement == 'bottom' && pos.top   + pos.height  + actualHeight - docScroll > parentHeight  ? 'top'    :
+                    placement == 'top'    && pos.top   - docScroll   - actualHeight < 0                         ? 'bottom' :
+                    placement == 'right'  && pos.right + actualWidth > parentWidth                              ? 'left'   :
+                    placement == 'left'   && pos.left  - actualWidth < parentLeft                               ? 'right'  :
+                    placement
+
+        $tip
+          .removeClass(orgPlacement)
+          .addClass(placement)
+      }
+
       switch (placement) {
         case 'bottom':
           tp = {top: pos.top + pos.height, left: pos.left + pos.width / 2 - actualWidth / 2}