Added db migration for link and link_url
Show if a post is a link on post#index
Adds link and link_url to trusted params
Adds link input-group to _form.html.erb

and fixes the glyphicons from bootstrap not showing up in the browser
Adds logic to post#blog to show embed link_url as p.title when p.link is true
Merge branch 'link' into stage
Adds .strftime to created_at for readability