Merge pull request #369 from osunyorg/mixin-article

assets/sass/_theme/blocks/posts.sass

assets/sass/_theme/sections/posts.sass

assets/sass/_theme/sections/programs.sass

assets/sass/_theme/sections/projects.sass

assets/sass/_theme/sections/volumes.sass

assets/sass/_theme/utils/shame.sass

layouts/partials/blocks/templates/pages.html

layouts/partials/blocks/templates/posts/highlight.html

layouts/partials/posts/post.html

layouts/partials/projects/project.html

layouts/partials/volumes/volume.html