refactor: use babel for compiling client code

[alexander-akait]

This PR contains a:

• bugfix
• new feature
• code refactor
• test update
• typo fix
• metadata update

Motivation / Use-Case

use babel for client hmr code

Breaking Changes

No

Additional Info

No

[codecov]

Codecov Report

Merging #396 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master     #396   +/-   ##
=======================================
  Coverage   65.19%   65.19%           
=======================================
  Files           4        4           
  Lines         408      408           
  Branches       84       84           
=======================================
  Hits          266      266           
  Misses        118      118           
  Partials       24       24

Impacted Files	Coverage Δ
src/hmr/hotModuleReplacement.js	0% <0%> (ø)	⬆️

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