scdbackup-0.8 released

New as (hopefully) stable features :
* Verification of write success and media readability
* Set of commands for writing on DVD (additional to the old commands for writing on CD)
* Incremental backups enhanced by checksums, list of vanished files
* Large File Support (depending on afio and mkisofs)
* Simplified upgrade from previous versions by FETCH_CONFIGURATION
* With incremental backups -max_size and some other options can be overridden