Basic folder loading.
Fixed infinite recursion.

Loading folders still doesn't create tree structure.
Merge fixes from 'master' into 'folders'.
Loading folders to tree structure. Many bugs.
Fix: don't refresh GUI for every file loaded.

Also made sure folders get expanded and columns resized properly.
Don't refresh GUI on click if item is already selected.
Removed unnecessary debug output.
Fix: checking for modified items on closing
Merge branch 'folders' into 'master'