Convert to future print syntax.

dstat_interface/interface/exp_int.py

@@ -16,6 +16,7 @@
 #     
 #     You should have received a copy of the GNU General Public License
 #     along with this program.  If not, see <http://www.gnu.org/licenses/>.
+from __future__ import division, absolute_import, print_function, unicode_literals
 
 import os
 import sys
@@ -26,7 +27,7 @@ try:
     gi.require_version('Gtk', '3.0')
     from gi.repository import Gtk, GObject
 except ImportError:
-    print "ERR: GTK not available"
+    print("ERR: GTK not available")
     sys.exit(1)
 
 import dstat_comm