[rt10000] Update to babel v7

[cristian-spiescu]

Hi there,

Do you see any issue in upgrading from babel 6 to babel 7? The storybook already works w/ babel 7 and I didn't notice any issues.

The motivation is this issue. Having 2 '.babelrc' files makes cumbersome the work w/ storybook.

[eliza-marcu]

We have added PR https://github.com/React9k/react-timeline-9000/pull/272 for this issue.

[cristian-spiescu]

Thanks for merging. Closing the issue.