Import and manage QGis "Orfeo Toolbox Provider" plugin as external plugin

Resume

As described in #2365 (closed) , the OTB provider plugin has been removed from QGIS Core. To ensure the compatibility with QGis, we have to manage the plugin internally as a third party maintained by OTB teams. The compatibility has been dropped in QGis 3.36.

Todo

• Create an OSGEO account to be able to publish the project. Do it before anything else as it may take time. https://www.osgeo.org/community/getting-started-osgeo/osgeo_userid/
• Create a git repository and import code from https://github.com/qgis/QGIS/tree/ltr-3_34/python/plugins/otbprovider ensure that everything needed has been copied (see https://github.com/qgis/QGIS/pull/55406/files)
• Be able to compile module, help can be found here https://plugins.qgis.org/ . This "plugin template" project can be a starting point https://plugins.qgis.org/plugins/pluginbuilder3/
• Before submitting the project, check that we respect every requirements listed by qgis https://plugins.qgis.org/publish/
• Submit the project at https://plugins.qgis.org/accounts/login/?next=/plugins/add/
• Update the cookbook doc https://www.orfeo-toolbox.org/CookBook/QGISInterface.html