Add history as top-level dependency
Add history as top-level dependency

Half-pulled in by npm 2.14.12 due to scroll-behavior peerDependency,
which caused the webpack build to fail when it couldn't find history's
dependency 'warning.' This does not happen in npm 3.x because all 
dependencies are installed at top level.
rothfels/gatsby,Khaledgarbaya/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,mingaldrichgan/gatsby,mingaldrichgan/gatsby,fabrictech/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,fabrictech/gatsby,gatsbyjs/gatsby,mingaldrichgan/gatsby,mickeyreiss/gatsby,fabrictech/gatsby,danielfarrell/gatsby,okcoker/gatsby,Khaledgarbaya/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,0x80/gatsby,fk/gatsby,fk/gatsby,chiedo/gatsby,ChristopherBiscardi/gatsby,okcoker/gatsby,rothfels/gatsby,danielfarrell/gatsby,mickeyreiss/gatsby,fk/gatsby,mickeyreiss/gatsby,Khaledgarbaya/gatsby,chiedo/gatsby,gatsbyjs/gatsby,okcoker/gatsby,ChristopherBiscardi/gatsby,danielfarrell/gatsby,0x80/gatsby,chiedo/gatsby,0x80/gatsby