Sidebar markup tweaks

 - Replaced nonsensical <ul> with <div id="bio">
 - Replaced <hr>s with borders
 - Removed extra wrapper <div> around social
Merge pull request #12 from coyotebush/sidebar

Sidebar markup tweaks
Merge remote-tracking branch 'upstream/master'

Conflicts:
	_includes/sidebar.html
Merge branch 'master' of https://github.com/cofiem/cofiem.github.io