update mathjax
merge from openwebwork develop
merging changes to js library directory
change permissions
Merge branch 'develop' of https://github.com/openwebwork/webwork2 into develop
Merge branch 'develop' of https://github.com/openwebwork/webwork2 into develop
Merge branch 'develop' of https://github.com/ionparticle/webwork2 into develop
Merge pull request #48 from ionparticle/develop

math4 theme improvements
Merge branch 'develop' of https://github.com/openwebwork/webwork2 into develop
Merge pull request #50 from mgage/develop

Develop