0.29.0

This release adds an OpenSearch client, as well as updates ISO parsing by removing longstanding deprecations/warnings. Users are advised to use 0.28.1 if previous ISO parsing workflows support is required.

A full list of commits for 0.29.0 can be found at:

https://github.com/geopython/OWSLib/commits/0.29.0:

• BREAKING: remove ISO deprecations (#862) (#869)
• add OpenSearch client implementation
• safeguard WMS GetMap bgcolor parameter (@geographika)
• fix WMS dimension parsing (@emilianocastaneda)