add mooc classes for android
Added Codility to interactive tutorials
Merge pull request #1214 from grogy/codility

Added Codility to problem sets
fix style nit
Merge pull request #1221 from ekeitho/master

add mooc classes for android
Merge pull request #1 from vhf/master

Update with vhf master
Add Linux succintly
Merge pull request #1222 from levibostian/master

Add Linux succintly