Merge pull request #53 from stecd/design

Design
added authentication for delete and edit
Merge pull request #54 from yutakahoulette/thursday_night

added authentication for delete and edit
added logo
added logo
merge issues
nav
styled alerts
changed user name placeholder
added intro to sections images
little fixes on content/section page
fixed buttons on courses show page
added enrollment link and model
fixed height
finished course show
index page image
final changes to index
browse