Py3k: arclink `futurize -0 -w .`
Py3k: passing most arclink tests on 27 and 33

The following test_decrypt fail in master and thus also in this branch on
my box.
* test_getWaveformNoPassword (obspy.arclink.tests.test_decrypt.ClientTestCase)
* test_getWaveformUnknownUser (obspy.arclink.tests.test_decrypt.ClientTestCase)
* test_getWaveformWrongPassword (obspy.arclink.tests.test_decrypt.ClientTestCase)