Coursera and edX, the two major providers of massive open online courses, continue to partner with more institutions. On Tuesday, edX, a nonprofit started with money from Harvard University and the Massachusetts Institute of Technology, announced it has 15 new partners, including a half dozen in Asia. Both edX and Coursera, a Silicon Valley-based company, have recently touted the global nature of their efforts. Coursera last week gained a prestigious domestic partner: Yale University, which had been taking its time to reflect.