Run against multiple environments on Travis CI
Adapt test script for py3k compatibility
Merge pull request #54 from sjakobi/py3k-travis

Adapt test script for py3k compatibility
Make hamming exercise compatible
Merge pull request #55 from sjakobi/py3k-hamming

Make hamming exercise compatible
Make matrix exercise compatible with Python3
Merge pull request #56 from sjakobi/py3k-matrix

Make matrix exercise compatible with Python3
Make rna-transcription exercise compatible with Python3
Merge pull request #57 from sjakobi/py3k-rna-transcription

Make rna-transcription exercise compatible with Python3
Make crypto-square exercise compatible with Python3

The behavior of str.translate and str(ing).maketrans is
very different in Python3. It turned out to be simpler to
replace the method by a simple custom function (_cleanse).

The other changes were introduced by a run of autopep8.
Make ocr-numbers exercise compatible with Python3
Make hexadecimal exercise compatible with Python3
Merge pull request #58 from sjakobi/py3k-crypto-square

Make crypto-square exercise compatible with Python3
Merge pull request #59 from sjakobi/py3k-ocr-numbers

Make ocr-numbers exercise compatible with Python3
Merge pull request #60 from sjakobi/py3k-hexadecimal

Make hexadecimal exercise compatible with Python3
Make wordy exercise compatible with Python3
Merge pull request #61 from sjakobi/py3k-wordy

Make wordy exercise compatible with Python3
Make trinary exercise compatible with Python3
Merge pull request #62 from sjakobi/py3k-trinary

Make trinary exercise compatible with Python3
Make pythagorean-triplet exercise compatible with Python3