This commit adds a default (ZSDOS) system image to all disk images that didn't already have a system image in their boot tracks.
- Enables the disk label to be displayed by SLABEL and the Slices Inventory functions for all disk images.
- Enables all disk images to have a basic boot mechanism allowing things like automatic batch processing to be added to any disk image.
- Changed "ws4" disk image to "wp" to reflect the fact that the disk image has multiple word processing distribuitions (WordStar 4 in user area 0 and ZDE in user area 1).
- Determine slice images to create dynamically based on the hd_xxx.txt and fd_xxx.txt files.
- Add a volume label directive to the hd_xxx.txt and fd_xxx.txt files.
- Add a system image directive to the hd_xxx.txt and fd_xxx.txt files.
