security/py-ecdsa: Correctly enable Python 3.x support
ecdsa module already (0.11) supports Python 3.x  and has just been
tested on Python 3.4 .
Correctly enable Python 3.x support accordingly.
White I'm here, whitespace align.
QA under Python 3.4:
Ran 43 tests in 10.659s - OK
5922 tests of inverse_mod completed. 0 errors detected.
Approved by: portmgr (blanket)