add rendering for 404.html when running zola serve

Fixed name in Image Processing page

Add home plug to snapcraft.yml

This should fix permissions errors when initializing or writing files.

Fix typo

Closes #537

Update brew docs

Closes #521

Closes #533

Update snap installation instructions

If you don't install with classic confinement, you'll get permission errors trying to create sites with `zola init`.

Add instructions on how to deploy to GitLab pages

Fix #525

Remove redundant clone

Updated install instructions

Changed arch linux from h2 to h3

I updated the install instructions (snap, scoop, chocolatey) and added the ones where Gutenberg already got renamed to Zola also to the top of the document.

Should yaourt be replaced by one of the other aur-helpers (pikaur, yay,...) as the development for it is stalled/discontinued for quite some time now although it is still working?

Scoop: https://github.com/lukesampson/scoop/blob/master/bucket/zola.json
Chocolatey: https://chocolatey.org/packages/zola
Snap: https://snapcraft.io/zola

Fix typo (missing 's')

Fix snapcraft build

Add missing pkg-config for finding openssl to snapcraft.yaml

Spells breadcrumbs correctly

0.5.0