v0.4.1
	* Changed pixmap directory to $prefix/share/pixmaps/graphopt
v0.4
	* Added postscript export
	* Made the pixmaps install correctly
v0.3
	* Changed default spring length to 0 and default spring constant to 1
	* Made dot file import more robust:
	  * Reports if it doesn't seem to be a dot file rather than blindly
	    trying to open it
	  * Accounts for more dot syntax
	  * doesn't segfault on any of the graphviz examples
	* Made graphopt file opening more robust:
	  * Reports if it doesn't seem to be a graphopt file rather than 
	    blindly trying to open it
	
v0.2
	* Changed references to vector to std::vector, making compliant with 
	  latest c++ standards (a la gcc 3)