standardise page structure

assets/sass/_theme/_configuration.sass

assets/sass/_theme/blocks/video.sass

assets/sass/_theme/design-system/layout.sass

assets/sass/_theme/sections/organizations.sass

assets/sass/_theme/sections/posts.sass

layouts/_default/list.html

layouts/_default/single.html

layouts/administrators/list.html

layouts/administrators/term.html

layouts/authors/list.html

layouts/authors/term.html

layouts/categories/list.html

layouts/categories/term.html

layouts/diplomas/list.html

layouts/diplomas/term.html

layouts/index.html

layouts/organizations/list.html

layouts/organizations/single.html

layouts/pages/list.html

layouts/papers/list.html