Add some of the final touches to the readme pending a check on github

Adjust the permission required in the manage template view logic

Make sure debug is set to False

Add login required and permission granted functions and mixins to block unauthorised users from certain pages

Add robots.txt and sitemap.xml to the root directory

fix some errors on the readme, add a little more content

Continue improving and adding resources and images to the readme

Add feature images to the readme, link feature section to index, link user stories to features

Fix for webhook error 500

Fix image tag media urls in wishlist, fix the small screen alert on order history to show only on small screens when there are previous orders to display

Improve the styling of the book detail page

Imrove the styling of the poster product detail page, removing a lot of unnecessary bootstrap classes

Tweak home and products styling accross screen sizes

Tweak the homepage for very long screens

Tweak homepage style to fix squashed elements on wider but shorter laptop screens