Value Tree Debugger with more features

[AdamVenn]

• Added standard gitignore to repo.
• Added a CmakeLists for Cmake users.
• Reworked the Value Tree Debugger to includes extra editing features and view types.
• Updated readme to include screenshots and more details.

[AdamVenn]

I wasn't quite sure how to include this code:

#ifdef JCF_SERIALIZER

    /* Code for handling valuetree serialization classes I use internally.
        They allow ReferenceCountedObjects that are stored in the tree
        to save, load and display debug information easily. You won't
        need this but it makes my life easier to leave it here - Jim. */
    if (t[name].isObject())
    {
        ReferenceCountedObject* p = t[name].getObject();

        if (Serializable* s = dynamic_cast<Serializable*> (p))
            propertyValue = "[[" + s->getDebugInformation() + "]]";
    }

#endif

Happy to get that back in if needed.