Revamped styling for all components

[kidunot89]

Styles are pre-processed and applied to individual view layer components, and structured in the same directory as the view. Global styles are located in the root directory in global-scss directory.

Styles to be completed:
post.scss - shared by page.jsx and post.jsx
post-comments.scss - comment area
comments.scss - comment
edit-comment.scss - comment form
login.scss - login form
main.scss - site main
menu.scss - navigation menu
header.scss - header component
user-controls.scss - logged in user controls
error.scss - error component
loading.scss - loading component