Update ideal4a.hs

Wow!  With valence set to 3 (not 2.5 or 3.5) and some weird version of fail merging (Composite fail-pre fail-post) + (Composite intended-pre intended-post) --> (Composite intended-pre fail-post), I get pained-pained-pleased for Environment041

Alas, the official version (and Martin's Python version) both learn Env041 given 100 runs :(.  Something's still wrong, but better than I thought.