Added missing javadoc to DataType methods. Issue #26.
Added missing javadoc to DataType methods. Issue #26.

CompEvol/beast2,Anaphory/beast2,tgvaughan/beast2,CompEvol/beast2,CompEvol/beast2,tgvaughan/beast2,tgvaughan/beast2,Anaphory/beast2,Anaphory/beast2,Anaphory/beast2,CompEvol/beast2,tgvaughan/beast2