windows: changed tcp port from glrpc assigned to unassigned one

On Windows 7 with MS Sharepoint Workspace installed test_stream failed with 10048 - WSAEADDRINUSE
Tcp port 9080 is occupied with glrpc service and can't be binded with SO_EXCLUSIVEADDRUSE option.

<pre>
test 17
      Start 17: test_stream

17: Test command: C:\WORK\GITHUB\0MQ\dev\b\bin\test_stream.exe
17: Test timeout computed to be: 9.99988e+006
17: Assertion failed: rc == 0, file C:\WORK\GITHUB\0MQ\dev\libzmq\tests\test_stream.cpp, line 175
</pre>

Here the list of IANA assigned ports http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?&page=110

With this pull request I've changed 9080 to unassigned 9070.