added read field to Link and migrations: marks Links as read on unread
added names to login and logout urls
added bootstrap. first base template and first link_list integration
Merge branch 'master' into use-bootstrap
some style changes on link_list template
added link to "Link List" from nav. added link_list url name
added brand link on navbar
added conditionally active class on navbar item possibility
Merge branch 'use-bootstrap'
added category list view, template and url