Update README.md

There can be only one introduction
Merge pull request #3 from jswetzen/master

Small fix for the README, trying out github!
L1 videos added
Minor fixes
Removed an incorrect description
Added new tutorial on Friday + link to gitbook
Added link to sample project
schedule update
Added links to git slides
Added android videos
Added link to the playlist for the git lecture
Added email addresses to Max and Erik, closing #5.
Added slides dir
Added slides
Update README.md
Update
Merge branch 'master' of https://github.com/morganericsson/DAT255
Dead links
Added videos
Added lecture 3 slides