Removed the concept of edges in favor of a proper tree-style approach, with each vertex knowing about its neighbors. This seems to have broken both Grah::crosses_edge() and Graph::remove_vertex. and the move radius circle doesn't draw any more. Go team.

drawutils.cpp

@@ -52,6 +52,7 @@ bool DrawUtils::draw(SDL_Surface* dest, SDL_Surface* drawable, int x, int y,
     return true;
 }
 
+#include "debug.h"
 void DrawUtils::draw_line(SDL_Surface* dest, Sint16 x1, Sint16 y1, Sint16 x2, Sint16 y2, Uint16 width, Uint32 colour)
 {
     float dx, dy, len;