refactor(jqLite): remove jqLite show/hide support

it turns out that even with our tricks, jqLite#show is not usable in
practice and definitely not on par with jQuery. so rather than
introducing half-baked apis which introduce issues, I'm removing them.

I also removed show/hide uses from docs, since they are not needed.

Breaks jqLite.hide/jqLite.show which are no longer available.

src/Angular.js

@@ -63,7 +63,6 @@ var _undefined        = undefined,
     $boolean          = 'boolean',
     $console          = 'console',
     $date             = 'date',
-    $display          = 'display',
     $length           = 'length',
     $name             = 'name',
     $noop             = 'noop',

src/directives.js

@@ -710,7 +710,7 @@ angularDirective("ng:class-even", ngClass(function(i){return i % 2 === 1;}));
 angularDirective("ng:show", function(expression, element){
   return function(element){
     this.$watch(expression, function(scope, value){
-      toBoolean(value) ? element.show() : element.hide();
+      element.css('display', toBoolean(value) ? '' : 'none');
     });
   };
 });
@@ -751,7 +751,7 @@ angularDirective("ng:show", function(expression, element){
 angularDirective("ng:hide", function(expression, element){
   return function(element){
     this.$watch(expression, function(scope, value){
-      toBoolean(value) ? element.hide() : element.show();
+      element.css('display', toBoolean(value) ? 'none' : '');
     });
   };
 });

src/jqLite.js

@@ -47,8 +47,6 @@
  * - [text()](http://api.jquery.com/text/)
  * - [trigger()](http://api.jquery.com/trigger/)
  * - [eq()](http://api.jquery.com/eq/)
- * - [show()](http://api.jquery.com/show/)
- * - [hide()](http://api.jquery.com/hide/)
  *
  * ## Additionally these methods extend the jQuery and  are available in both jQuery and jQuery lite
  * version:
@@ -456,32 +454,6 @@ forEach({
     return element.getElementsByTagName(selector);
   },
 
-  hide: function(element) {
-    if (element.style) {
-      if(element.style.display !=="none" && !JQLiteData(element,"olddisplay")) {
-        JQLiteData( element, "olddisplay", element.style.display);
-      }
-      element.style.display = "none";
-    }
-  },
-
-  show: function(element) {
-   if(element.style) {
-     var display = element.style.display;
-     if ( display === "" || display === "none" ) {
-
-       // restore the original value overwritten by hide if present or default to nothing (which
-       // will let browser correctly choose between 'inline' or 'block')
-       element.style.display = JQLiteData(element, "olddisplay") || "";
-
-       // if the previous didn't make the element visible then there are some cascading rules that
-       // are still hiding it, so let's default to 'block', which might be incorrect in case of
-       // elmenents that should be 'inline' by default, but oh well :-)
-       if (!isVisible([element])) element.style.display = "block";
-     }
-   }
-  },
-
   clone: JQLiteClone
 }, function(fn, name){
   /**