Update maintainers list

Adding myself to the maintainers' list for the official telegraf docker images, for future releases.

Tagging @reimda @powersj @MyaLongmire @sspaink @srebhan to +1  if required.

library/telegraf

@@ -2,7 +2,8 @@ Maintainers: David Reimschussel <[email protected]> (@reimda),
              Josh Powers <[email protected]> (@powersj),
              Mya Longmire <[email protected]> (@MyaLongmire),
              Sebastian Spaink <[email protected]> (@sspaink),
-             Sven Rebhan <[email protected]> (@srebhan)
+             Sven Rebhan <[email protected]> (@srebhan),
+             Alan Pope <[email protected]> (@popey)
 GitRepo: https://github.com/influxdata/influxdata-docker.git
 GitCommit: 1cec93ead66bb9ca4a1e34a2070dfafba3b9c7a9