Port tests to python 3

tests/twisted/cm/protocols.py

tests/twisted/connect/twice-to-same-account.py

tests/twisted/gabbletest.py

tests/twisted/roster/groups.py

tests/twisted/sasl/telepathy-password.py

tests/twisted/servicetest.py

tools/c-constants-gen.py

tools/glib-ginterface-gen.py

tools/glib-gtypes-generator.py

tools/glib-interfaces-gen.py

tools/glib-signals-marshal-gen.py

tools/libglibcodegen.py

tools/libtpcodegen.py

tools/make-release-mail.py