Cosmetic code changes.
Outsource array functions.
Finish to replace and remove useless sort functions with array_sort_key.
Modify array sort function.
Begin to replace and remove useless sort functions with array_sort_key.
Add universal array_sort_key function.
Rename functions.
Refactor code. Make it more maintainable.
Add API functions to handle configured disks. Helps to keep code maintainable.
Only display not already configured disks in dropdown list.
