flake8: check for mutable function parameters

install flake8-mutable (and, just to be sure, flake8-builtins;) to check
for these things, as reported in #38.

Author: igalic

.travis.yml

@@ -5,7 +5,7 @@ sudo: false
 env:
   - MYPYPATH="$TRAVIS_BUILD_DIR/.travis/mypy-stubs"
 install:
-  - pip3 install flake8 mypy
+  - pip3 install flake8-mutable flake8-builtins mypy
 script:
   - ".travis/flake8.sh"
   - mypy iocage

.travis/flake8.sh

@@ -2,7 +2,7 @@
 # Run pep8 on all .py files in all subfolders
 
 tmpafter=$(mktemp)
-find ./libiocage/ -name \*.py -exec flake8 --ignore=E203,W391 {} + | grep -v "./libiocage/__init__.py" > ${tmpafter}
+find ./iocage/ -name \*.py -exec flake8 --ignore=E203,W391 {} + | grep -v "./iocage/__init__.py" > ${tmpafter}
 num_errors_after=`cat ${tmpafter} | wc -l`
 echo "Current Error Count: ${num_errors_after}"
 echo "Current Errors:"
@@ -17,7 +17,7 @@ echo "Comparing with last stable release: ${last_release}"
 git checkout ${last_release}
 
 tmpbefore=$(mktemp)
-find ./libiocage/ -name \*.py -exec flake8 --ignore=E203,W391 {} + | grep -v "./libiocage/__init__.py" > ${tmpbefore}
+find ./iocage/ -name \*.py -exec flake8 --ignore=E203,W391 {} + | grep -v "./libiocage/__init__.py" > ${tmpbefore}
 num_errors_before=`cat ${tmpbefore} | wc -l`
 echo "${last_release}'s Error Count: ${num_errors_before}"