python-markupsafe: add recipe

MarkupSafe is a Python library for escaping HTML strings, and it is a
dependency for Jinja2.  Add a recipe to build it.

Copied from commit 6ba88a72843826370773cda29309545c7c800dc0 in
meta-cloud-services/meta-openstack and updated to version 0.23.

Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>