Add filters

[manthanhd]

Filters are functions that can be run before the request makes it to the skills. This is pre-classification so the filter can get the basic metadata like the sentence etc.

A filter once set runs for every call, every time.

var myfilter = new RequestFilter(function(context, request, response, next) {
    ...
    return next();
});

[manthanhd]

At what point does a filter get executed?

[manthanhd]

Filters can be configured at bot creation time. Something in options like this:

{
    filters: [sentenceSplitterFilter, badWordsFilter]
}

Filters can be executed immediately when the bot receives a resolution request. They can help modify request or response objects.

This work can be split into two pieces:

1. Add the ability for people to add filters in general while keeping the multiple sentences bit in.
2. Extract multiple sentence parser into its own filter.