Some general fixes and improvements

[therippa]

This addresses a few of the issues you opened on the project, and makes some improvements...

1. Allows for registration via text (just text "join")
2. Makes voice configurable
3. Adds support for sending an MMS message to the group
4. Handles impatient people texting the couple for updates
5. Fixes some speech pacing and cadence issues
6. Adds distinctive labor/born updates phrases (labor sends a text, born text and calls...I imagine people who choose the call option don't care about the more granular updates)
7. More custom message

Thanks for your work on this, it saved me some time from having to write it from scratch!