New Webchat Client

I've been working on a new version of the webchat client for a couple of weeks, mainly to reduce duplication of the function call to the server, but also in response to a couple of users asking how they could change the default question presented when the bot starts.

This has been addressed on startup of the client by first asking the question YINITIALQUESTION. If this grammar exists, typically a random list of initial responses, it returns the response, otherwise it returns the value for initial_question in config.yaml.

No changes should be required as long as you have one or both of the following defined in config.yaml

bot:
    initial_question: Hi, how can I help you today?
    initial_question_srai: YINITIALQUESTION

Also in this release

learn and learnf now replace the existing template now if one exists. This was an error in the initial understanding of how learn and learnf work which affected how aimlstandardlibrary processed certain grammars