Auto merge of #2764 - micbou:fix-directory-creation-travis, r=bstaletic

[READY] Fix Linux builds on Travis

Travis complains that the `/home/travis/bin` folder already exist when creating it. Use `mkdir` with the `-p` option.

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ci/travis/travis_install.linux.sh

@@ -3,7 +3,7 @@
 # We can't use sudo, so we have to approximate the behaviour of setting the
 # default system compiler.
 
-mkdir ${HOME}/bin
+mkdir -p ${HOME}/bin
 
 ln -s /usr/bin/g++-4.8 ${HOME}/bin/c++
 ln -s /usr/bin/gcc-4.8 ${HOME}/bin/cc

ci/travis/travis_install.sh

@@ -15,14 +15,15 @@ source ci/travis/travis_install.${TRAVIS_OS_NAME}.sh
 # pyenv setup
 #############
 
-export PYENV_ROOT="${HOME}/.pyenv"
+PYENV_ROOT="${HOME}/.pyenv"
 
 if [ ! -d "${PYENV_ROOT}/.git" ]; then
+  rm -rf ${PYENV_ROOT}
   git clone https://github.com/yyuu/pyenv.git ${PYENV_ROOT}
 fi
 pushd ${PYENV_ROOT}
 git fetch --tags
-git checkout v20160202
+git checkout v1.0.8
 popd
 
 export PATH="${PYENV_ROOT}/bin:${PATH}"