[Delta] iris compilation error on GCC 4.7

[Bartosz Brachaczek]

Hi,

iris fails to compile on GCC 4.7:

   src/irisnet/corelib/netinterface_unix.cpp:134:15: error: ‘close’
was not declared in this scope

After including the <unistd.h> header in that file, compilation succeeds.

Cheers,
Bartosz Brachaczek