Deprecate chatbot keyword body parameter

[aaronschachter]

FEATURE OVERVIEW

User Story

As an ODev - I want the chatbot request to query Contentful for a matching keyword using the args body parameter instead of keyword.

This needs to be featured flagged via environment variable, so we can continue to rely on the keyword parameter in production (whenever the flag is not set)

https://www.pivotaltracker.com/story/show/146382529

Additional Information

There will need to be tweaks made for the Completed Campaign Menu Message -- we currently prompt members to text {{keyword}} {{cmd_reportback}} if they want to report back again. Mobile Commons sends that request as: { keyword: BUMBLEBOT, args: START }. This is a hack because of how often we send messages that place members into Agent View (Broadcasts, Reminder Messages) -- eventually won't need the hack once chatbot no longer sending members into Agent View for those instances.

Why This Matters

• Consolebot will be more useful for testing (#933), can eventually add Slack
• Remove extra step of Campaign configuration by adding keywords to our mData

Current Workaround w/o Feature (if applicable)

N/A

[aaronschachter]

This will be handled by #939