Content feed update

Features:
     - Issue following is now possible.
     - The frontpage has been redesigned for non-registered users.
     - The frontpage is now a content feed for registered users.
     - Fixed major authentication bug in the api.
     - Centralized all essential components, like dropdowns in a single file. (components.css)
     - Added better error handling: form errors and action errors.
     - Bug fixes.