Added radio icons

Fixes issue #13
fixed visual issues
fixed visual issues
Merge branch 'issue/12' of https://github.com/adaptlearning/adapt-contrib-mcq into issue/12
Merge pull request #15 from adaptlearning/issue/12

fixed visual issues
Merge pull request #14 from zenduo/develop

Added radio icons
Merge pull request #16 from adaptlearning/develop

Develop