By Steve Lohr March 17, 2015 6:00 am March 17, 2015 6:00 am When IBM announced its partnership with Twitter last October, the move seemed both promising and logical. IBM is betting a fair share of its future on exploiting large troves of data for its business customers, and Twitter is a big-data fire-hose with 6,000 tweets a second, more than half a billion each day. And Twitter’s data-licensing b