allow passing AC_PATH from environment
Merge pull request #316 from adamv/homebrew

allow passing AC_PATH from environment
searn much faster with --quiet now
fixed bug
fixed stupid bug
Merge branch 'master' of git://github.com/JohnLangford/vowpal_wabbit
Merge pull request #317 from hal3/master

searn faster with --quiet
fix spurious l1 prediction mode
Merge branch 'master' of github.com:JohnLangford/vowpal_wabbit
Merge branch 'master' of git://github.com/JohnLangford/vowpal_wabbit

merge with jl master
vw-top-errors: better comments + add copyright/licence notes (same as vw)
Avoid uninitialized warnings on too few features or deviant examples
Switch to mean-of-weights by default.  Add -s option for sum-of-weights