[clike mode] Add a better Objective C demo

Shows off some newer Objective C features and makes "visual" testing
new features easier.

Author: dmaclach

mode/clike/index.html

@@ -147,16 +147,36 @@ <h2>Objective-C example</h2>
 That spans two lines
 */
 
-#import <Test/Test.h>
+#import "MyClass.h"
+#import <AFramework/AFrameork.h>
+@import BFrameworkModule;
+
+NS_ENUM(SomeValues) {
+  aValue = 1;
+};
+
+// A Class Extension with some properties
+@interface MyClass ()<AProtocol>
+@property(atomic, readwrite, assign) NSInteger anInt;
+@property(nonatomic, strong, nullable) NSString *aString;
+@end
+
 @implementation YourAppDelegate
 
-// This is a one-line comment
+- (instancetype)initWithString:(NSString *)aStringVar {
+  if ((self = [super init])) {
+    aString = aStringVar;
+  }
+  return self;
+}
 
-- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{
-  char myString[] = "This is a C character array";
-  int test = 5;
-  return YES;
+- (BOOL)doSomething:(float)progress {
+  NSString *myString = @"This is a ObjC string %f ";
+  myString = [[NSString stringWithFormat:myString, progress] stringByAppendingString:self.aString];
+  return myString.length > 100 ? NO : YES;
 }
+
+@end
 </textarea></div>
 
 <h2>Java example</h2>