Footer redesign

[akronb]

Changes in this PR:

• Gave the footer a new look
• Made sure the footer stays at the bottom on all pages
• Cleaned up some unused styles
• Removed the content class (since the header already has bottom padding, no need for extra padding)
• Now, we're grabbing the year directly from Hugo

Redesign

Desktop

| ```before``` |  | |--------|--------| | ```after``` |  |

Tablet

| ```before``` | ```after``` | |--------|--------| |  |  |

Mobile

| ```before``` | ```after``` | |--------|--------| |  |  |

How to quickly check it:

I suggest visiting the /nettest/facebook-messenger/ URL to view all the changes at once.