Recode the system's utility ls.
To-do:
- add pipe handling
- add sorting (at least aplhabetical)
- add -i flag for print (print file ID)
- add -d flag (list directory itself)
- add -F flag (classificator)
- add -g flag (in long list, do not print owner)
- add flags mentioned in 'print.c' file
- add -m flag (print all files as comma-separated)
- add -o flag (like l+G)
- add -x flag (list by lines instead of columns) (may be hard)
IDEA FOR SPEED IMPROVEMENT: read files' stat() in print section, only when needed (with -l flag);