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Solves an IE11 issue with react-split-pane, see
storybookjs/storybook#298 (comment)

Author: shockey

package.json

@@ -41,6 +41,7 @@
   },
   "dependencies": {
     "boron": "^0.2.3",
+    "bowser": "1.6.1",
     "classnames": "^2.1.3",
     "core-js": "^2.4.1",
     "immutable": "^3.x.x",