Display Cluster Name on Dashboard header and display cluster_info in one page

[Yui-Song]

Feature Request

Is your feature request related to a problem? Please describe:

1. Typically, a DBA will manage bunch of databases and sometimes work on multiple database clusters at the same time. It would be very useful and helpful if the cluster name could be display in a conspicuous place on Dashboard.
2. It would be nice if cluster_info can be displayed in one page, so that users can get all the cluster information with only 1 click. It is more user-friendly when the network latency is high.

Describe the feature you'd like:

[breezewish]

@lilyjazz Please take a look about the suggestion. Thanks!