code: boolean resolveBooleanExpression(String expression, Entity entity) {
      return resolveBooleanExpressions(singletonList(expression), entity).get(0);
    }
docs: Resolves a boolean expression (validation or visible expression)
  
  @param expression JavaScript expression
  @param entity entity used during expression evaluation
  @return <code>true</code> or <code>false</code>
  @throws MolgenisDataException if the script resolves to null or to a non boolean