rsf-contactable

The primary handler for mapping different configuration types to different Contactable carrier implementations

Supported carrier Contactable implementations so far:

• rsf-smsable: phone -> Smsable, will speak to and listen to someone at a given phone number, via Twilio APIs
• rsf-mattermostable: mattermost -> Mattermostable, will speak and listen to someone at a given username at a given Mattermost server
• rsf-telegramable: telegram -> Telegramable, will speak and listen to someone at a given username on Telegram