Enhance About Us Section

[troynguyen8]

Enhanced About Us section by:

• adding link in nav to "about us" section.
• adding icons and metrics to measure our impact
• rephrasing our description, including subtext about a few things that make us unique

Changed Nav by:

• increasing contrast. There is no longer transparency on the links. Instead, they are white by default, and on hover they are grey.
• Changing the expand icon on screen widths to be white. Changed the "hamburger" icon to use font awesome instead of default SVG specified in bootstrap

Changed Our Clubs Section:

• Added subtext about what our clubs are

Desktop:

Tablet (iPad):

Mobile (iPhone X):

closes #41

[troynguyen8]

@justinjstark How does it look now? It's worth noting that the navbar does odd text wrapping currently with screen widths in the range of 730 - 770 px (notably effects the original iPad and modern iPad minis). I will add a fix for this in #47 via a priority nav, since we are only going to add more navigation links.