style updates
added styles for pre and code tags
change normal font-weight from 300 to 400
switching font-family to Open Sans
style updates
changed font-family to Roboto
replacing markdown.js with pagedown, updated styles
added rainbow syntax highlighting
change rainbow's comment to brighter color for readability
reduced padding-top of first post
added slug to post urls
reduce m2m calls for PostListView by retrieving relevant Tags in a single call