graphics/py-OWSLib: Update to 0.17.1

While I'm here:

• Add path to license file

Changelog:

https://github.com/geopython/OWSLib/compare/0.17.0...0.17.1

PR: 236308
Submitted by: lbartoletti <lbartoletti@tuxfamily.org> (maintainer)
Approved by: tcberner (mentor)
Differential Revision: https://reviews.freebsd.org/D19518