Enhance texting api

[schroerbrian]

This PR addresses two issues:

1. It adds support to texting information about resources, which was not previously supported by this API. Resources are listed within our search results and receiving their information may be of interest to our user base; this PR enables this
2. Our texting API was not updated to reflect our support for services that have addresses, which are not inherited from their parent resource's primary address. I've added code that first checks if the selected service has an address and, if not, it falls back to the resource address

There is a corresponding front-end PR here; however, this PR should be able to be merged without breaking the current setup

[richardxia]

LGTM, aside one minor comment about getting the texting parameters from the already processed data rather than directly from the HTTP parameters!