Fix parsing the track padding

[pnedkov]

When PADTRACKS=n the trac padding is 3 digits

[pnedkov]

When PADTRACKS is not set or it is set to n (which is the default) I get the following warning when abcde finishes:

$ abcde
Grabbing entire CD - tracks: 001 002 003 004 005 006 007 008 009 010 011 012
...
...
...
[WARNING] The encoded formats does not match with the moved ones
[WARNING] Formats encoded:
[WARNING] Formats moved: flac
[WARNING] Use "abcde -a clean -f -C a70d630c" to force the removal of the remaining data.
Finished. Not cleaning /home/plamen/abcde.a70d630c.

It looks like the track padding is 3 digits (001, 002, 003...).

Here is how the status file looks like:

abcde-version=2.9.1
cdparanoia-audio-tracks=12
Lookup method 0: cddb
cddb-statcomplete
cddb-querycomplete
cddb-read-1-complete
cddb-readcomplete
cddb-entries=1
cddb-choice=1
variousartists=
variousartiststyle=forward
cddb-edit
readtrack-001
encodetracklocation-%local1%=001
encodetrack-flac-001
encodetrack-001
tagtrack-flac-001
tagtrack-001
movetrack-001
movetrack-output-flac
readtrack-002
encodetracklocation-%local1%=002
encodetrack-flac-002
encodetrack-002
tagtrack-flac-002
tagtrack-002
movetrack-002
...

I am on Arch Linux.