hook: add a 'hashook' function to test for hook existence
Preparing the data for some hooks can be expensive. Add a function to check if
a hook exists so we can skip useless preparation if no hook is configured.
FROM fedora:21
RUN yum install -y \
gcc \
gettext \
make \
python-devel \
python-docutils \
rpm-build
# For creating repo meta data
RUN yum install -y createrepo