Update collectd README for Debian 9 support
@@ -43,7 +43,7 @@ The SignalFx collectd agent is supported on the following operating systems:
| Operating System | Version |
|-----------|----------------|
| Amazon Linux | 2014.09, 2015.03, 2015.09, & 2016.03 |
-| Debian | 7 & 8 |
+| Debian | 7, 8, & 9 |
| Mac OS X | 10.8+ |
| RHEL/Centos | 6.x & 7.x |
| Ubuntu | 12.04, 14.04, 15.04 & 16.04 |
