/// <summary>
/// Purges the specified asset from the content manager's internal cache.
/// </summary>
/// <param name="asset">The asset to purge from the cache.</param>
/// <param name="lowMemory">A value indicating whether the cache is being purged due to the operating system
/// being low on memory. If this value is <see langword="true"/>, then assets which have the
/// <see cref="AssetFlags.PreserveThroughLowMemory"/> flag will be ignored by this method. Otherwise,
/// all of the cache's assets will be purged.</param>
public void PurgeAsset(AssetID asset, Boolean lowMemory)
{
Contract.Ensure <ArgumentException>(asset.IsValid, nameof(asset));
PurgeAsset(AssetID.GetAssetPath(asset), lowMemory);
}