sim_fibo_ad: remove compatibility code for old parser

this makes the simulator quite a bit more maintainable: setting
USE_NEW_PARSER to 0 did not even compile after the the constructor for
the wells manager which took the old deck was removed last
week. Since, according to Atgeirr, SPE-1 is now producing exactly the
same results as before, it also does no longer make too much sense to
keep that code on life support...
Merge pull request #114 from andlaus/sim_fibo_ad_remove_old_parser

sim_fibo_ad: remove compatibility code for old parser