Improve datetime handling to ensure naive datetimes and update templates, imports, and docstrings

[liamjdavis]

This pull request focuses on improving the handling of datetime objects by ensuring they are naive (i.e., not timezone-aware) across various functions and modules. Additionally, it includes some minor changes to the HTML templates and imports.

Key Changes:

Datetime Handling Improvements:

• Added a make_naive function to ensure start_time and end_time are naive datetimes in parse_database.py and views.py. [1] [2]
• Updated add_event_markers to ensure start_time and end_time are naive datetimes.
• Modified generate_heatmap to remove the timezone parameter and ensure naive datetime handling.
• Updated filter_events to apply make_naive to events.
• Applied make_naive in various functions in views.py to ensure consistent datetime handling. [1] [2] [3]

Documentation Removal:

• Removed detailed docstrings from functions in generate_map.py and parse_database.py to streamline the code. [1] [2] [3] [4] [5]

HTML Template Update:

• Updated the default event image URL in home.html to a new link.

Import Cleanup:

• Removed unused imports from views.py and parse_database.py. [1] [2]

These changes collectively ensure better datetime handling and improve code maintainability by removing unnecessary documentation and imports.