Adding configurable telegraf parameters.
Allow to configurre remote endpoint/port/login/token
Proposed CLI:
```
set service monitoring
telegraf authentication login '
[email protected]'
set service monitoring
telegraf authentication token 'footokenfoo'
set service monitoring
telegraf url 'foo.local:8086'
set service monitoring
telegraf metrics daemons 'keepalived'
set service monitoring
telegraf metrics daemons 'sshd'
```