Error self signed cert

send Test email fail with error "self signed certificate"

tried with and without secure connection (port 25 and 787) 

using nodebb 0.9.3 and https://github.com/popu125/nodebb-plugin-emailer-local

```
4/1 18:09 [3090] - warn: [emailer.smtp] Unable to send `registration_accepted` email to uid 1!!
4/1 18:09 [3090] - error: [plugins] filter:email.send,  self signed certificate
```
