fixed jvm switch

The `Go To Server` button did not work as the [parseQueryString](https://github.com/hawtio/hawtio/blob/master/hawtio-web/src/main/webapp/app/core/js/corePlugin.ts#L9) seems to fail for hashbang urls. 

The url before:

`http://host:port#/?url=some.url`


The url now:

`http://host:port?url=some.url#some/frontend/route`