private IEnumerable <TagInfo> GetAllTags()
{
IEnumerable <ImageInfo> images = Repos
.SelectMany(repo => repo.Images)
.ToArray();
IEnumerable <TagInfo> sharedTags = images
.SelectMany(image => image.SharedTags);
IEnumerable <TagInfo> platformTags = images
.SelectMany(image => image.Platforms)
.SelectMany(platform => platform.Tags);
return(sharedTags
.Concat(platformTags)
.ToArray());
}