[WIP] Use workers to render pages in parallel

[agubler]

Type: feature

The following has been addressed in the PR:

• [x] There is a related issue
• [x] All code has been formatted with prettier as per the readme code style guidelines
• [x] Unit or Functional tests are included in the PR

Description:

Moves the build time rendering logic into a pool of workers in order to increase the performance by rendering the pages in parallel.

Resolves #184