FS-7323 #resolve #comment [mod_http_cache] added http_remove_cache <url> API call to manually expire a cached URL.
Added {refresh=true} parameter that can be prefixed to URL to force refresh when using http:// https:// file formats or the http_get API.
Examples:
    http_remove_cache http://phono.com/audio/troporocks.mp3
    http_get {refresh=true}http://phono.com/audio/troporocks.mp3
    <action application="playback" data="{refresh=true}http://phono.com/audio/troporocks.mp3"/>