travis: switched PyPy tests to squeaky/portable-pypy

.travis.yml

@@ -13,6 +13,9 @@ python:
   - 3.5
   - nightly
 
+before_install:
+  - "if [[ $TRAVIS_PYTHON_VERSION == 'pypy' ]]; then deactivate && wget https://bitbucket.org/squeaky/portable-pypy/downloads/pypy-5.7-linux_x86_64-portable.tar.bz2 && tar -jxvf pypy-5.7-linux_x86_64-portable.tar.bz2 && echo 'Setting up aliases...' && export PATH=$HOME/pypy-5.7-linux_x86_64-portable/bin/:$PATH && ln -s ~/pypy-5.7-linux_x86_64-portable/bin/pypy ~/bin/python && echo 'Setting up pip...' && pypy-5.7-linux_x86_64-portable/bin/pypy -m ensurepip ; fi"
+  - "if [[ $TRAVIS_PYTHON_VERSION == 'pypy3' ]]; then deactivate && wget https://bitbucket.org/squeaky/portable-pypy/downloads/pypy3.5-5.7-beta-linux_x86_64-portable.tar.bz2 && tar -jxvf pypy3.5-5.7-beta-linux_x86_64-portable.tar.bz2 && echo 'Setting up aliases...' && export PATH=$HOME/pypy3.5-5.7-beta-linux_x86_64-portable/bin/:$PATH && ln -s ~/pypy3.5-5.7-beta-linux_x86_64-portable/bin/pypy3.3 ~/bin/python && echo 'Setting up pip...' && pypy3.5-5.7-beta-linux_x86_64-portable/bin/pypy -m ensurepip && ln -s ~/pypy3.5-5.7-beta-linux_x86_64-portable/bin/pip3.5 ~/bin/pip ; fi"
 install:
   - travis_retry pip install coveralls
   - travis_retry pip install tox-travis