uplevel_chatredir v1.0.0

Proxy does a few functions

• anything with 'private' in the URL fails
• anything with a chat URL validates the HMAC, brings up the chat web page, injects content (i.e. first name)
• and some private things like generate random key for HMAC, creates URL based on name
• anything else throws an exception which makes it fallthrough to the server

Secrets to set

• HMAC_KEY
• LOGDNA_INGESTIONKEY
• ZENDESK_CHATAUTH_KEY