CDK-140: Add namespaces

The customer I visited with today almost exclusively uses external tables that are put into separate Hive databases based on the group that owns the data. That's also the main model for delegating authorization management in Sentry.

Can the pattern be:
```java
new URIPattern(
            "hive://" + hiveAuthority +
                "/*path/:dataset?absolute=true&namespace=:namespace" + hdfsAuthority);
```

Or is that what you meant by passing general URI options?