identify now takes care of UTC and makes real clusters.

the today.php give Localtime timestamps, but the mtime is in UTC, so only a few files were been identifyed correctly.
(this is a quick fix, better use proper libraries or let the server give utc)

during clustering lasttime wasn't set to the time of the last file, so every cluster only contained one file ;).

these two errors combined causes many files to not beeing identifyed.