[#master] Added VariableNode::getName() and setName()
Added hasParameter() convenience methods to ParameterTrait. (#81)
Wrote tests for the hasParameter() methods and fixed bugs uncovered by them.
Added one more assertion to check for FALSE case of hasParameter().
Added another test for InvalidArgumentException thrown by hasParameter().
Added another assertion for passing a newly created parameter to hasParameter().
Fixed hasParameter when passed ParameterNode
Made type optional
Merge pull request #82 from grom358/hasParameter

Has parameter