Done:
 - Save writes to a backup then overwrites old save
 - number of items displayed can be changed with new constant
 - gui divided into a more manageable 3 panels, add/remove buttons added
 - tree replaced hash for sorted lists
 - prevented empty Strings from making Entries
Program will now search the user list for inputed word, and return the
position in the list where it should be.

Todo:
 - Sort is lexicographical, need to make sure item names are lowercase
when they undergo sort, possibly make a 3rd field, "sortName"
 - add/remove buttons need their respective functions

Eventually:
 - Fix capitalization in masterIndex.txt file.
 - Convert display from an ArrayList of JLabels to a JList and allow
attributes of the item to be changed when selected.
 - Make the search dynamic so a search button wouldn't be needed