Mobile optimizations, style for links

Change flex-direction to column when mobile.

Background and border for header.

::after on links with Web Symbols. Tags get their own icon.
$post->title is enclosed in <h4>
Removed <menu type=list> an <li>'s from nav links
Custom curson and a variety of icons for different link types

Custom cursor for whole page (Arch).

Regular links get a link (as in chain).

Links with the target (need to further specify later) get something that
seems to indicate a new window or tab.

Anything with the download attribute gets an attachment icon.

Style for sidebar.
Added rel="tag" attribute to tags
Added rel="search" attribute to search input
Corrected canonical

Fixed typo.

Do not want URL alone for every page. Add REQUEST_URI.
Better rel and itemprop usage.

Set rel="bookmark" on the link for the home page.

Use itemprop=keywords on <nav> and rel=tag on all tags.
Update <link rel=canonical> on ajax with data.history
Set a few additional role attributes