Update README.md

Fixed link to repository
Merge pull request #1 from styx/patch-1

Update README.md
Update README.md

Fixed link to project's issues.
Merge pull request #2 from styx/patch-2

Update README.md
Removed some .DS_Store files.

Signed-off-by: Mikhail S. Pobolovets <styx.mp@gmail.com>
Added Code Climate badge.
Code highlighting in readme.
Merge pull request #3 from styx/master

Some updates
changed average calculation
Merge pull request #9 from jorjao/master

Changed the way average is calculated