switch to multipass being the default. still does the 1 pass approx independent from the multi pass run, good for comparing. No big perf issue. May eliminate the unnecessary run at some point (it's just 1 extra iteration). json has 'result' and 'result_single' now. At all times, the answer is in 'result' (multiple_pass = 0 or 1).
Merge branch 'master' of https://github.com/0xdata/h2o
Merge branch 'master' of https://github.com/0xdata/h2o