#3 Improvements to Mputil

[Lewis Jardine]

adds support for stored data files to mputil: doesn't
attempt to mpm/dempm them.
adds support for sending more than one file at once

adds the following commands to mputil:

decode/encode - convert mp3<>mpm
wipe - delete all mp3s (but not files) on device
format - format flash/smartmedia card

This patch depends on patch 989162

[Lewis Jardine]