graph_to_eps mission accomplished.
- lemon/graph_to_eps.h header created
- lemon/bezier.h: Tools to compute with bezier curves (unclean and undocumented
  interface, used internally by graph_to_eps.h)
- demo/graph_to_eps_demo.cc: a simple demo for lemon/graph_to_eps.h
     1 LEMON as a whole is copyrighted by Egerváry Jenő Kombinatorikus
 
     2 Optimalizálási Kutatócsoport (Egervary Combinatorial Optimization
 
     3 Research Group, EGRES).
 
     5 You are free to use, modify and distribute LEMON under the terms
 
     6 described in the LICENSE file.
 
     8 This project is supported by
 
    10 * Egyetemközi Távközlési és Informatikai Központ (Inter-University
 
    11   Centre for Telecommunications and Informatics, Hungary)
 
    13 * Traffic Analysis and Network Performance Laboratory,
 
    14   Ericsson Research, Hungary
 
    16 * Department of Operations Research, Eötvös Loránd University,