DC/OS input plugin reports unmarshal errors

[danielnelson]

Bug report

There are reports of errors when running the DC/OS plugin.

Relevant telegraf.conf:

System info:

Telegraf 1.5.2

Steps to reproduce:

1. enable dcos plugin
2. ???

Expected behavior:

No errors

Actual behavior:

E! Error in plugin [inputs.dcos]: 404 Not Found 
E! Error in plugin [inputs.dcos]: json: cannot unmarshal array into Go value of type dcos.Metrics 
E! Error in plugin [inputs.dcos]: 400 Bad Request 
E! Error in plugin [inputs.dcos]: 400 Bad Request 
E! Error in plugin [inputs.dcos]: took longer to collect than collection interval (10s) 
E! Error in plugin [inputs.dcos]: 400 Bad Request 
E! Error in plugin [inputs.dcos]: json: cannot unmarshal object into Go value of type []string 
E! Error in plugin [inputs.dcos]: json: cannot unmarshal object into Go value of type []string 
E! Error in plugin [inputs.dcos]: json: cannot unmarshal object into Go value of type []string 
E! Error in plugin [inputs.dcos]: 404 Not Found