Added Hide Stories option + Fixed Options for recommended channels and vieweres also watch

[ChrisScr3ams]

Proposed changes

Twitch recently introduced Stories to their page. These now have a dedicated button in the sidebar for them.
Since many users are not interested in these stories at all an option to hide this button from the sidebar should be added.
This new button also broke the already existing settings to hide recommended channels and channels that viewers also watch.
The functionality of these 2 settings should be fixed.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

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• I have read the CONTRIBUTING doc
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in downstream modules

Further comments

The option to hide the new Stories from the sidebar was pretty straight forward, because Twitch luckily used unique classnames for them.
The fix of the other 2 options is a bit ugly though.
Since the current implementation uses nth child calls to get to the correct divs (that's also the reason why they broke in the first place) and the number of children changes depending on if the sidebar is collapsed or expanded, even more nth child calls were neccessary. This is just a temporary quick fix though. A cleaner solution for a complete refactoring of the sidebar handling already exists by chips here #767