- add new argument for option -a and -p to append/prepend user-specified folder.
- modified help according to changes.
- changed
  * xpwd does folder number exist -> is_line_number_within_profile
  * is within profile -> is_folder_within_profile
- added new argument -i to show profile-info.
- removed unused functions.
- aligned output with printf.
- fixed bug when handling relative paths which will expand now correctly.