* enhancement: major performance increase by optimizing and merging top (SDL) and bottom (citro3D) screen update routines
* enhancement: reSID sound engine support. Default engine is fastSID for O3DS, reSID for N3DS. reSID is more performance-hungry that fastSID, but sound is by far better. To change this setting, open VICE menu and go to "Machine settings" -> "Model settings" -> "SID settings" -> "SID model"
* enhancement: new help screen to show all current button functions (in emu and in menu)
* enhancement: soft button positions can now be changed by activating edit-mode (VICE menu: "Misc" -> "Edit bottom screen button positions") and dragging the soft buttons with the stylus. New positions are saved when saving settings
* enhancement: applying default setting will not require restart anymore
* enhancement: config files (vicerc, ROMs, icons etc.) are stored internally per default, files on SD card override internal files. Added menu entry in "Settings" menu to copy all internal config files to SD card.
* optimization: remove SDL joystick - all 3ds buttons and pad directions are now "keys" for vice3DS. These keys can be mapped to C64-joysticks via definition of keysets.
* optimization: define all default settings in code, no sdl-vicerc config file needed anymore
* optimization: optimize compiler flags for speed
* bugfix: eliminated sound distortions when using bottom screen (result of performance increase)
* bugfix: some soft buttons wouldn't unstick, fixed bug in MaxScreen softbutton
* multiple other small enhancements, optimizations and bug fixes