fix: added babel transform-object-assign to fix IE support

[Pwntastic]

Using native Object.assign was breaking IE support, so I pulled in babel-plugin-transform-object-assign to add in a polyfill when necessary.

Also the linter was complaining about the quotes around TRACE so I fixed that too.

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@539dab5). Click here to learn what that means.
The diff coverage is 0%.

@@           Coverage Diff           @@
##             master   #255   +/-   ##
=======================================
  Coverage          ?    82%           
=======================================
  Files             ?      5           
  Lines             ?    150           
  Branches          ?      0           
=======================================
  Hits              ?    123           
  Misses            ?     27           
  Partials          ?      0

Impacted Files	Coverage Δ
src/core.js	73.33% <0%> (ø)

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[cyberhck]

what's going on with this one? why is this PR not merged?

[Pwntastic]

Is there anything that I specifically need to do?

[cyberhck]

it almost looks like author of this repo didn't even look at this PR 😄

BTW to make tests pass, you need to ADD some tests, reason those are failing is because redux-logger doesn't have enough test coverage.

[z-vr]

just spent an hour figuring it out, can this be merged please.