Added Value Field to the Bot Message Sampler Used for handling Adaptive Cards submit

[newlogics]

This Change will add a new field to the Bot Message Sampler. This allows JSON Vey value pairs to be sent as Activity Value to handle Adaptive Cards submit.

Fix for issue #7

Currently, there is no way to send a reply to the below sample Adaptive card which might become a blocker but with this change Activity values can be directly sent through the sampler.

{
    "type": "AdaptiveCard",
    "$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
    "version": "1.2",
    "body": [
        {
            "type": "TextBlock",
            "text": "Name:",
            "wrap": true
        },
        {
            "type": "Input.Text",
            "placeholder": "Placeholder text",
            "id": "Name"
        }
    ],
    "actions": [
        {
            "type": "Action.Submit",
            "title": "Submit"
        }
    ]
}

Thanks,
Palanikumar

[newlogics]

@damadei Could you please review and Approve the Pull request