add guards in config.h to avoid multiple inclusions
add guards in config.h to avoid multiple inclusions

raster: may I rename elementary_config.h to config.h ? If I
add macros for all the init stuff, it would be nice to have
consistent name for that file


SVN revision: 55952

FlorentRevest/Elementary,tasn/elementary,tasn/elementary,FlorentRevest/Elementary,rvandegrift/elementary,rvandegrift/elementary,FlorentRevest/Elementary,tasn/elementary,tasn/elementary,FlorentRevest/Elementary,rvandegrift/elementary,tasn/elementary,rvandegrift/elementary