Fix of host/port getters, that are used by BoshConfiguration

Somewhy getters for host/port are used private host and port fields that were written only from setUsedHostAddress method. Because those weren't written from ctor, then you instantiate BoshConfiguration with it's ctor it's getURI() method returned incorrect URI with null host and 0 port.
Instead of patching BoshConfiguration it was logical to patch ConnectionConfiguration since those getters are the only plase where host/port were used, so I naturally removed them.

After doing this I'm able to connect to my bosh server without using setUsedHostAddress method.