add test_extensions.c the nua_test build on windows
add test_extensions.c the nua_test build on windows

darcs-hash:20061121135415-16063-df730c02d8ae78a6303d7846f28d4aeb116884cd.gz

unispeech/sofia-sip,erdincay/sofia-sip,BelledonneCommunications/sofia-sip,unispeech/sofia-sip,BelledonneCommunications/sofia-sip,xhook/sofia-sip,BelledonneCommunications/sofia-sip,erdincay/sofia-sip,erdincay/sofia-sip,xhook/sofia-sip,jart/sofia-sip,erdincay/sofia-sip,xhook/sofia-sip,unispeech/sofia-sip,xhook/sofia-sip,BelledonneCommunications/sofia-sip,xhook/sofia-sip,unispeech/sofia-sip,jart/sofia-sip,jart/sofia-sip