Comments should not be removed

[cherifGsoul]

Fix #138

This keeps comments with their methods and classes:
Transforms:

// Model subtask
const Subtask = DefineMap.extend("Subtask",{
    // parentTodo should not be serialized
    parentTodo: {serialize: false, type: "any"},
    // a save utility that actually saves the parent todo
    save(){
        this.parentTodo.save();
    }
});

to:

// Model subtask
class Subtask extends ObservableObject {
    static get props() {
        return {
            // parentTodo should not be serialized
            parentTodo: {enumerable: false, type: type.Any}
        };
    }

    // a save utility that actually saves the parent todo
    save() {
        this.parentTodo.save();
    }

    static get propertyDefaults() {
        return DeepObservable;
    }
};

[phillipskevin]

Do comments inside functions (and getters) already work?