confirm unload if form is dirty
Avoid reloading FetchedData on every re-render.
Make unsaved changes use react state.
This adds the flexibility to display something on unsaved changes and have multiple components with unsaved changes.
Make the FetchedData prop name configurable.
getDefaultProps must not reference this.props in React 0.11.
Use defaultValue rather than value to fix form.
Merge remote-tracking branch 'origin/master' into 1559-confirm-unload-if-dirty
Merge pull request #381 from ENCODE-DCC/1559-confirm-unload-if-dirty

1559: Add form unload protection