Version 2.10.0:
* Attribute filter - Allow to have a comma separated list of groups or users,
for Lizmap Web Client 3.8 and PostgreSQL layer
* Add tests with a FILTER with apostrophe
* Add log if the relation was not found when generating the tooltip
Version 2.9.4:
* API key - check for Google or Bing layers without an API key
* Avoid a critical error message which was not needed
* Add missing LICENSE file
Version 2.9.2:
* Review the `GetLegendGraphic` request about invalid layer, not only for
vector
* Improve logging about invalid layer
