Travis CI build failing for Python 3.3

[veeresht]

• File "/home/travis/build/veeresht/CommPy/commpy/init.py", line 17, in
  from filters import *
  ImportError: No module named 'filters'
• commpy/channelcoding/algcode NotPython: Couldn't parse '/home/travis/build/veeresht/CommPy/commpy/channelcoding/algcode.py' as Python source: 'invalid syntax' at line 35
• commpy/channelcoding/gfields NotPython: Couldn't parse '/home/travis/build/veeresht/CommPy/commpy/channelcoding/gfields.py' as Python source: 'invalid syntax' at line 63
• commpy/channelcoding/tests/test_convcode NotPython: Couldn't parse '/home/travis/build/veeresht/CommPy/commpy/channelcoding/tests/test_convcode.py' as Python source: 'invalid token' at line 17

[quantumdude836]

Prefixing commpy. to all the import statements fixed the ImportError for me. Tested with python 3.5.1 on Ubuntu 16.04.