Reorganize Preferences
Update dirent.h win32 implementation
Add default Doxyfile
Set up Doxyfile
Sample code docs for challengeauth_response()
Add structs and use treeview
Temporary workaround for reconnect crashes on win32

Yes, we really need to fix this ASAP
Use png instead of svg
Improve sort keybinding in servlist

also disable auto sorting on fav channels, closes #606