Many changes, added symlinking and data saving

Use shutil instead of os modules, using ctypes for the Windows API, load
and save data with csv module
Added alt+key menu navigation
Loads past and current history data from files at startup
Save histories after new symlink
Added missing dialog titles and messages
Renamed path and location variables. Path is folder tree a file/folder
is in, location is the path with the file/folder name.

Also includes symlink_manager.bat to run main.py with elevated
permissions.