@NonNull
    private ImmutableTriple<Bitmap, Metadata, Boolean> loadCachedImage(final File file, final boolean forceKeep) {
        if (file.isFile()) {
            return loadCachedImage(Uri.fromFile(file), forceKeep, file.lastModified());
        }
        return ImmutableTriple.of(null, null, false);
    }
Load a previously saved image.

@param file      the file on disk
@param forceKeep keep the image if it is there, without checking its freshness
@return a triplet with image in the first component, Metadata in second (only if loadMetadata=true) and
{@code true} in the third component if the image was there and is fresh enough or {@code false} otherwise,
and the image (possibly {@code null} if the third component is {@code false} and the image
could not be loaded, or if the third component is {@code true} and {@code onlySave} is also
{@code true})
main/src/main/java/cgeo/geocaching/network/HtmlImage.java