Added Value.hasChildren, for checking if a value has sub-elements.
Added Value.hasChildren, for checking if a value has sub-elements.

jolie-projects/jolie-async,innopolis-jolie-smt-typechecker/jolie,agwe/jolie,agwe/jolie,innopolis-jolie-smt-typechecker/jolie,mawolf/jolie,innopolis-jolie-smt-typechecker/jolie,jolie-projects/jolie-async,jolie-projects/jolie-async,innopolis-jolie-smt-typechecker/jolie,mawolf/jolie,mawolf/jolie,agwe/jolie,jolie-projects/jolie-async,mawolf/jolie,agwe/jolie