Better local dev environment + footer layout fix

[rafaelconde]

What does this PR do?

• Makes footer sticky to the bottom of page;
  • Compare before and after
• Adds a local server with browser sync and auto refresh (check README for instructions);
• Changes absolute to relative file paths for easier development environment

Can I preview these changes live?

Sure you can, just visit this link: Preview

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I am really sorry for the big PR, I just wanted to fix the footer and then I cloned the repo and felt powerless without browser sync 😅 , and then the URLs weren't working, so I changed the paths…

┓┏┓┏┓┃
┛┗┛┗┛┃＼○／
┓┏┓┏┓┃ / SCOPE CREEP
┛┗┛┗┛┃ノ)
┓┏┓┏┓┃
┛┗┛┗┛┃
┓┏┓┏┓┃
┛┗┛┗┛┃
┓┏┓┏┓┃
┃┃┃┃┃┃
┻┻┻┻┻┻

[rafaelconde]

Also, totally unrelated, but have you consider pushing this to Netlify (I know I'm bias), but it offers free HTTPS, global CDN, and it can get pretty faster 💙