[Feature] - Styling Overhaul

[quintindunn]

Since the site is still in heavy development the styling of the site looks nothing short of disgusting. While the current priority should be making the site functional, when we're waiting for a new feature to add to the site we should be working on styling the site.

I believe the order this should be done in is the following:

1. Core template (i.e. ./templates/core/core.html ./static/core/css/core.css)
2. Sub templates (i.e. ./templates/vector2d/vector_template.html)
3. Children of sub templates (i.e. ./templates/vector2d/vector_addition_calculator.html ./static/vector2d/css/vector_addition_calculator/vector_addition_calculator.css)

[quintindunn]

Added some basic styling and content to 2dvectors home page.