Add constant fractions to code

src/stars/Eagle/stars_part.h

 /*******************************************************************************
  * This file is part of SWIFT.
  * Copyright (c) 2016 Matthieu Schaller (matthieu.schaller@durham.ac.uk)
-<<<<<<< HEAD
  *               2018 Folkert Nobels (nobels@strw.leidenuniv.nl)
-=======
->>>>>>> Add Eagle stars
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU Lesser General Public License as published
@@ -126,6 +123,12 @@ struct stars_props {
 
   /*! Maximal change of h over one time-step */
   float log_max_h_change;
+
+  /*! Fixed mass ratio Ca to Si */
+  float Ca_to_Si;
+  
+  /*! Fixed mass ratio S to Si */
+  float S_to_Si;
 };
 
 #endif /* SWIFT_EAGLE_STAR_PART_H */