Collector no options no newline

1.  diamond::collector breaks if you don't define at least 1 option.   Now able to to specify no options.

```
diamond::collector { 'RedisCollector': }
```

2.  collector.conf is generated with newlines after each entry.  Removing those lines.

```
enabled=True
  a=xxx
  b=yyy
  c=zzz

vs.

enabled=True

  a=xxx

  b=yyy

  c=zzz
```