Refactoring Frog interface so I can use it as an external library later: added declarations to Frog.h, introduced FrogOptions class to hold the various options (rather than global variables) 


git-svn-id: https://ilk.uvt.nl/svn/sources/Frog/trunk@17613 12f355fe-0486-481a-ad91-c297ab22b4e3