Improve default cache expiration settings


  1. After the code review of the CacheServiceFactory class we've figured out that SlidingExpiration setting is not passed to Fuse8.DomainFramework.CacheService.TagHttpCacheService when it is created.
    We need to fix that.
  2. By default, when both sliding expiration and absolute expiration are not specified in the Web.config, the CacheService is created without any expiration. This behavior should be changed... presumably to 20 minutes absolute expiration. But we may need to discuss this.
Both fixes should be done in CacheServiceFactory.InitCacheService method.