feat(readme): Add travis build badge
feat(readme): Add travis build badge

cferrios/react-grid-layout,vpezeshkian/react-grid-layout,cferrios/react-grid-layout,cferrios/react-grid-layout,vpezeshkian/react-grid-layout,STRML/react-grid-layout,vpezeshkian/react-grid-layout,STRML/react-grid-layout,STRML/react-grid-layout