Create Javadocs

[tim-tran]

On everything

[ryfurrer]

@lionkingsimba If you haven't yet. I'll do my activities and the data manager class

[ryfurrer]

After the code is documented a javadoc pdf should be made and added to github

[tim-tran]

I haven't done Javadocs for your stuff yet. Yiji said that java docs only need to be done for entity (model) classes and methods. So I don't think the javadocs for activites need to be done.
However, she did say that if we do add javadocs for extra stuff, it would count towards out "overall quality" mark.