Minor refactoring

[theobat]

Another bunch of refactorings for component based builds. This is mostly about creating data types instead of tuples and removing unnecessary indirection in tasks configure options

Note: Fixes for the online documentation of the current Stack release (https://docs.haskellstack.org/en/stable/) should target the 'stable' branch, not the 'master' branch.

Please include the following checklist in your pull request:

• [X] Any changes that could be relevant to users have been recorded in ChangeLog.md.
• [X] The documentation has been updated, if necessary

Please also shortly describe how you tested your change. Bonus points for added tests!

[mpilgrem]

I merged manually, after some reformatting for consistency.