Add header images when available to general and news feeds

[bgtripp]

Changes

• Added function to find image url from feedparser dictionary objects
• Used said function to assign value of "image" key for items in the general and news feeds
• Adjusted template to allow for display of header images if they are found
• Added custom css to display images properly

[sonarcloud]

SonarCloud Quality Gate failed.

0 Bugs
0 Vulnerabilities (and 0 Security Hotspots to review)
0 Code Smells

No Coverage information
34.1% Duplication

[bgtripp]

Sorry for closing and reopening, I'm new to working on open source projects! It seems like these checks are failing from pre-existing code in the project. Also, that duplication rule is a little strict when that one block copied between two templates is a third of my new lines haha. Let me know if you need me to edit it :)