Issue 6625 - Expose webpack's resolve.alias to the packagers

tests/README.md

 # Buildtools unit tests
 
 ## Introduction
 
 Unit tests for buildtools, using the pytest framework.
 
 ## Approach
 
 In order to test the buildtools capability of creating WebExtension-packages
 for Chrome, Edge and Firefox, an example configuration for each platform is
@@ skipping 25 matching lines @@
 - Inlcusion of defined contentScripts into the manifest (CEF)
 - Packaging (and moving) of included icons / scripts / HTML files (CEF)
 - Presence of files for all configured locales (CEF)
 - Correct import of translations with or without placeholders, with or without
   access keys (CEF)
 - Translation presence and validity for the Chrome Web Store (C)
 - Packaging of modularized script files with webpack (CEF)
 - Adherence to provided build-number in the manifest (CEF)
 - Other content in the manifest (CEF)
 - Correct encrypted signature of the package (C)
+- Exposure of webpack's module aliasing machinery
 
 ## Requirements
 
 - [Tox](https://pypi.python.org/pypi/tox) (>= 2.7.0)
 
 _(Tox will take care of installing the other dependencies such as flake8 and
 flake8-abp inside a virtualenv.)_
 
 ## Usage
 
 To run the tests simply run
 
 ```
 $ tox
 ```
 
 in the buildtools' root folder.
 
 ## Coverage
 
 Pytest will create a coverage report as output to the terminal, using the
 pytest plugin `pytest-cov`.
 
 In order to get an html report you can add `--cov-report=html` to the
 pytest-command in tox.ini.
 
 For more information please refer to the
 [coverage documentation](https://coverage.readthedocs.io/)