Make regression tests work again. Fix Travis CI.
Make regression tests work again. Fix Travis CI.

aaronmars/vexflow,Silverwolf90/vexflow,Silverwolf90/vexflow,Huji/vexflow,aaronmars/vexflow,Silverwolf90/vexflow,Huji/vexflow,Tails/vexflow,Huji/vexflow,aaronmars/vexflow,Tails/vexflow,Tails/vexflow