Upgrade npm on Travis to support ^ syntax.
Upgrade npm on Travis to support ^ syntax.

rafaelstz/regenerator,rafaelstz/regenerator,juliocanares/regenerator,sebmck/regenerator,liviuignat/regenerator,sebmck/regenerator,facebook/regenerator,facebook/regenerator,juliocanares/regenerator,RReverser/js-goto-transpiler,Jericho25/regenerator,liviuignat/regenerator,RReverser/js-goto-transpiler,Jericho25/regenerator,kittens/regenerator,facebook/regenerator,kittens/regenerator