Added several more HTML5 samples

src/site/samples/appcache/example/appcache.dart

+import "dart:html" as j;class n{static const  o="Chrome";static const  q="Firefox";static const  s="Internet Explorer";static const  t="Opera";static const  u="Safari";final  k;final  minimumVersion;const n(this.k,[this.minimumVersion]);}class v{const v();}class AB{final  name;const AB(this.name);}class BB{const BB();}class CB{const CB();}class DB{var g;DB(this.g){g.onCached.listen(h);g.onChecking.listen(h);g.onDownloading.listen(h);g.onError.listen(l);g.onNoUpdate.listen(h);g.onObsolete.listen(h);g.onProgress.listen(h);g.onUpdateReady.listen((i)=>m());} m(){if(g.status==j.ApplicationCache.UPDATEREADY){g.swapCache();j.window.alert('A new version of this site is available. Please reload.');}} h( i){print('Cache event: ${i}');} l( i){j.window.alert("Oh no! A cache error occurred: ${i}");print('Cache error: ${i}');}} main(){new DB(j.window.applicationCache);}