More usability

• Added support for saving a file to its load/previously saved location. You no longer have to specify the path every time you make a little change.
• Added keybinds to undo and redo
• Fixed renamed tabs resetting the folding
• Remove LATEST entry from the SNbt popups
• Changed the number picker to be more uniform. Also has a context menu to quickly set the min/max value.
• Fixed a crash if a component name contains [ or ]