Rough working implementation of JTree for folders
Miscellaneous code cleanup
Fixed "Toggle All" button
Fixed a mishap in pre-patching code
Fixed node transfer handler...

...to not allow directories to be dragged into themselves.
Fixed a fringe-case with node transfer...

...that would still allow directories to be dragged into themselves.
Fixed mod order not being remembered correctly

ModFolderInfo's internal lists were never updated to match the most
recent state of the JTree
Fixed transfer being allowed over empty space
Fixed transfer not being allowed into empty folders
Code cleanup, readability
Merge pull request #1 from kartoFlane/tree

Tree