Deleting intellij files and creating .gitignore file

@thaishamilton, 


I removed some intellij files. It was hard to look at your commits because of them :). Also, I added the .gitignore file. After your merge this pull request and pull it in your repo, you'll see that will break your intellij project. This is ok. You just need to import it again. File -> Import Project -> Select CaelumExercises folder  and it should be fine. 

I also removed the "out" folder, which is the folder where intellij put the compiled classes. However, if you run your tests again, you'll see that git is not ignoring the "out" folder yet. Can you make it ignore this folder? 

Talk to you on Monday. Have a nice weekend :)