Asynchronous refactor || Project Modernisation

[noopkat]

Description

Simplified many code flows in this library for better readability.

Type of change

Please delete options that are not relevant.

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [x] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [x] This change requires a documentation update

Checklist:

• [ ] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass locally with my changes
• [x] Any dependent changes have been merged and published in downstream modules
• [x] Changes have been manually tested (please provide information on test platform using the fields below)

[coveralls]

Coverage increased (+29.07%) to 75.758% when pulling 13bf2f8aba26e0f66e421cff4ca7eb854df18ba1 on remove-async-dep into 4c88107415fec46eacabf81fb2fb8a6f271b7828 on master.