add iDigBio API (#881)

README.md

@@ -631,6 +631,7 @@ API | Description | Auth | HTTPS | CORS |
 |---|---|---|---|---|
 | [arcsecond.io](https://api.arcsecond.io/) | Multiple astronomy data sources | No | Yes | Unknown |
 | [CORE](https://core.ac.uk/services#api) | Access the world's Open Access research papers | `apiKey` | Yes | Unknown |
+| [iDigBio](https://github.com/idigbio/idigbio-search-api/wiki) | Access millions of museum specimens from organizations around the world | No | Yes | Unknown |
 | [inspirehep.net](https://inspirehep.net/info/hep/api?ln=en) | High Energy Physics info. system | No | Yes | Unknown |
 | [Launch Library](https://launchlibrary.net/docs/1.3/api.html) | Upcoming Space Launches | No | Yes | Unknown |
 | [Minor Planet Center](http://www.asterank.com/mpc) | Asterank.com Information | No | No | Unknown |