Added a selectable list of items to the browser and options for sorting.

Changes:

- reduced the item list storage to one treemap
- browser tab now works as an item browser, will show all items in the
masterIndex.txt file, clicking on them will show the item attributes to
 the right.  Layout for the tab is mostly complete, but sorting has not
yet been implemented.

todo:
- search is broken again, if an item is in the masterIndex but not the 
userIndex, it will not display the item immediately above it, will still
 add items properly though.
- finish the browser tab so that the list changed depending on settings
at the bottom.