Change rollup config

[emmatown]

What:

• Remove all the individual rollup configs and create a single one in the root directory
• Add babel-plugin-transform-es2015-typeof-symbol to babel-preset-env excludes

Why:

Because there was lots of duplication and if we wanted to change the babel config we had to go to every rollup config and change it.

I removed babel-plugin-transform-es2015-typeof-symbol because we aren't checking if something is a symbol so it adds a useless helper.

How:

Checklist:

• Documentation N/A
• Tests N/A
• Code complete

[codecov-io]

Codecov Report

Merging #280 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #280   +/-   ##
=======================================
  Coverage   90.37%   90.37%           
=======================================
  Files          21       21           
  Lines         966      966           
  Branches      260      260           
=======================================
  Hits          873      873           
  Misses         75       75           
  Partials       18       18

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