examples: make teardown.sh osx compatible
examples: make teardown.sh osx compatible

* FIX Makes `rm` call osx compatible. (closes #104)

Signed-off-by: Diego Rodriguez <288245649d05cf8f96289b2b35cece8d6bcb04be@cern.ch>

tiborsimko/invenio-access,inveniosoftware/invenio-access,inveniosoftware/invenio-access,tiborsimko/invenio-access