added "run-tests" and "pre-commit"

"run-test" is a script, that performs all tests in the current work
tree. This should be executed during development.

"pre-commit" is a wrapper arount "run-test" such, that it can be
symlinked to serve as a git pre-commit hook. Doing so will ensure to run
all tests before commiting. The wrapper also stashes changes that will not
be commited and restores them afterwards.

pre-commit

@@ -0,0 +1,33 @@
+#!/bin/bash
+
+# This script is a wrapper around the run-tests script.
+# It is highly recommended to link it as the git pre-commit hook via:
+
+# ln -s ../../pre-commit .git/hooks/pre-commit
+
+# The difference to the run-tests script is that this script stashes
+# unstaged changes before testing (see below). Thus only the changeset to be
+# commited will be tested. No worries, "git commit -a" will still work ;)
+# Stephan Kuschel, 2014
+
+# Stash unstaged changes if and only if(!) necessary (=possible):
+# if you dont check that you might uninentionally apply an older stash,
+# because this if statement just makes sure, that there are changed to
+# be stashed on executing "git staph -q --keep-index". Otherwise it coud
+# happen, that git stash is executed, but no stash is created, because
+# there were no changes, that could be stashed.
+if git diff-index --quiet HEAD --; then
+    #echo "pre-commit hook without stashing"
+    ./run-tests
+    exitcode=$?
+else
+    #echo "pre-commit hook with stashing"
+    git stash -q --keep-index
+    ./run-tests
+    exitcode=$?
+    git stash pop -q
+fi
+
+
+exit $exitcode
+

run-tests

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+# run all tests and pep8 changes of this project.
+
+# For development, please see pre-commit for
+# instructions how to add this as a git pre-commit hook.
+
+# Stephan Kuschel, 2014
+
+exitonfailure () {
+    if [ $1 -ne 0 ]; then
+        echo '"./run-tests" failed. Aborting.'
+        exit $1
+    fi
+}
+
+# run actual tests
+nosetests
+exitonfailure $?
+
+pep8 postpic --statistics --count --show-source --ignore=W391
+exitonfailure $?
+
+exit 0
+