Update all dependencies

[amgadfahmi]

Thank @rikschennink for this great library, this an update for all the dependencies. Please find a breakdown of the changes below:

• uses babel 7 and all the plugins has been updated to latest. es2015 is now preset-env
• plugin-external-helpers is no longer need as stated by Babel

  Using "external-helpers" plugin with rollup-plugin-babel is deprecated, as it now automatically deduplicates your Babel helpers

• browserslist is now configured in .browserslistrc file in the root directory and it will be auto picked by autoprefixer
• new task in build will update the files used by the example folder
• npm run dev will now start a web server on port 3001

Saw your comments about changing the build tool, something like parcel would be nice, might do it later on if this can help.

Another benefit now the flip.min.js is 1kb less in size 😃