Update Layout Examples to ASDK 2.0 (#2551)

* Objective-c project updated to ASDK 2.0

* fix assets error

* [LayoutSpecExamples] Renamed new example project to be easier to type / find.

* [Bulid] Manually create Sample.xcscheme file to hopefully fix complaining bulid :).

* clean up project

* commentary on ASAbsoluteLayoutSpec

* address @maicki's comments

examples/LayoutSpecExamples/Sample/OverviewCellNode.m

@@ -0,0 +1,53 @@
+//
+//  OverviewCellNode.m
+//  Sample
+//
+//  Copyright (c) 2014-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+
+#import "OverviewCellNode.h"
+#import "LayoutExampleNodes.h"
+#import "Utilities.h"
+
+@interface OverviewCellNode ()
+@property (nonatomic, strong) ASTextNode *titleNode;
+@property (nonatomic, strong) ASTextNode *descriptionNode;
+@end
+
+@implementation OverviewCellNode
+
+- (instancetype)initWithLayoutExampleClass:(Class)layoutExampleClass
+{
+    self = [super init];
+    if (self) {
+      self.automaticallyManagesSubnodes = YES;
+      
+      _layoutExampleClass = layoutExampleClass;
+      
+      _titleNode = [[ASTextNode alloc] init];
+      _titleNode.attributedText = [NSAttributedString attributedStringWithString:[layoutExampleClass title]
+                                                                  fontSize:16
+                                                                     color:[UIColor blackColor]];
+  
+      _descriptionNode = [[ASTextNode alloc] init];
+      _descriptionNode.attributedText = [NSAttributedString attributedStringWithString:[layoutExampleClass descriptionTitle]
+                                                                              fontSize:12
+                                                                                 color:[UIColor lightGrayColor]];
+   }
+    return self;
+}
+
+- (ASLayoutSpec *)layoutSpecThatFits:(ASSizeRange)constrainedSize
+{
+    ASStackLayoutSpec *verticalStackSpec = [ASStackLayoutSpec verticalStackLayoutSpec];
+    verticalStackSpec.alignItems = ASStackLayoutAlignItemsStart;
+    verticalStackSpec.spacing = 5.0;
+    verticalStackSpec.children = @[self.titleNode, self.descriptionNode];
+    
+    return [ASInsetLayoutSpec insetLayoutSpecWithInsets:UIEdgeInsetsMake(10, 16, 10, 10) child:verticalStackSpec];
+}
+
+@end