Merged pages branch into source branch

- Added the following Gems that can be used with GitLab Pages natively (actually,
  anything can be used with GitLab Pages and their shared runners setup. No more
  safe mode Jekyll for me 😃)
  - jemoji
  - jekyll-paginate
  - jekyll-gist
  - jekyll-redirect-from
  - jekyll-sitemap
- Removed the pages.rb plugin and moved the pages into the Pages folder so that
  Jekyll would process them.
- Removed the redirect pages and added the necessary YAML frontmatter for the
  jekyll-redirect-from gem
- Removed the RSS Feed xsl and css files
- Removed the need for the Rakefile, Gruntfile etc
- Put the css into a sass file so Jekyll could combine them itself and added the
  sas declarations to _config.yml
- Removed the sitemap.xml file in lieu of the jekyll-sitemap gem
- Removed the defunct javascript files
- Removed the CNAME file as it isn't needed in GitLab
- Changed back to the old Flickr plugin as it seems to work better
- Added site.baseurl to a couple of the asset links as best practice
4 jobs for pages
Status Name Job ID Coverage
  Deploy
passed pages #1059691

00:04:00

passed pages:deploy

00:00:07

passed pages #1059620

00:03:04

passed pages:deploy

00:00:06