Tagging release: version 2.3

New Features:
   *  New command ':toggle <register> command-list', which allows the
      user to quickly toggle through a list of commands.  This is useful
      for switching through sort and display schemas that one may
      frequently use.
   *  New command-line option '-c command' to execute command in a
      currently running instance of vitunes.  The command specified can
      be either a run-time command or keybinding.  This makes it easy to
      control vitunes from other windows or applications.
      Thanks to @knk for this.
   *  New command ':playlist name' allowing one to load a named playlist.
      Thanks to @knk for this.
   *  Volume level can now be controlled via vitunes.  Default keybindings
      are '<' &amp; '>' for volume up/down, respectively.
   *  New colorable item 'current-inactive', allowing you to specify the
      color of the current row in the window without focus.
   *  Playlists with unsaved changes now have a '+' preceeding their name
      in the Library window, more like regular vim.

Bug-Fixes:
   *  Linux build corrected.
   *  Allow running vitunes with no playlists.
   *  Memory leak patch.  Thanks to @altenmueller.
   *  Many small bugfixes and performance improvements.
   *  Much improved man page.

Cleaned up website info in the man page.

Simple work-around for some still man-page weirdness.

Update developer doc to reflect recent changes, including the splitti…

…ng of

keybdindings/run-time-commands out of input_handers.* and into their own
files.

Update todo-list to more accurately describe 8-color to 256-color goal.