added host/port/pid file configs to readme

- Access on http://localhost:9000

##Configuration

You can further customize Cerebro by editing its conf/application.conf file.

Some settings in cerebro can be set by specifying them as Java System properties, while others need to be specified on the configuration file(conf/application.conf).

For an extensive list of Java System properties accepted, check https://www.playframework.com/documentation/2.5.x/ProductionConfiguration

### HTTP server address and port

You can run cerebro listening on a different port(9000) and host(0.0.0.0):

```

bin/cerebro -Dhttp.port=1234 -Dhttp.address=127.0.0.1

```

### Path of RUNNING_PID

By default, the RUNNING_PID is placed on the root directory of cerebro, but it is recommendable to place it somewhere that is cleared on restart(/var/run). Make sure the location exists and that cerebro has write permissions to it.

```

bin/cerebro -Dpidfile.path=/var/run/cerebro.pid

```

It is also possible to avoid the creation of the RUNNING_PID file by setting the path to /dev/null on the configuration file:

```yaml

pidfile.path = "/dev/null"

```

###List of known hosts

A list of predefined hosts can be defined for quicker access. If host is password protected, authentication should be also set.

A list of predefined hosts can be defined for quicker access by editing conf/application.conf file. If host is password protected, authentication should be also set.

Example: