Feature Request: CachedFileSearchPath

Hi JUCE team,

Would it be possible and reasonable to have a CachedFileSearchPath in the framework? You load it once in memory and then operate on it until you call ::invalidate/redo etc.

For example I have this scenario where I have many audio files coupled with images, searching for the image of each audio file requires a full traverse of the selected locations added to the FileSearchPath which takes quite a long time. (profiled)

I hope this is a reasonable request.