##For use image without cache, you can use the method: + (nullable CHImage *)imageNamedWithoutCache:(NSString *)name;
##For use image with cache, and add the cache to the default group "-1": + (nullable CHImage *)imageNamedByCache:(NSString *)name;
##For use image with cache, and add the cache to the customize group.this like for,when you exit to a viewController, and you only want to clear images of this viewController used. so you can add these images to a customize group and clear the group when you exit. + (nullable CHImage *)imageNamedByCache:(NSString *)name namespace:(NSString *)ns;
##For clear image by name: - (void)clearImageCachedByName:(NSString *)name;
##For clear images in group: - (void)clearImageCached:(NSString *)ns;
##For clear all images cache: - (void)clearAllImageCached;
##Reference: