Update the documentation about Remote Modules

Target documentation resources

Documentation about the Remote Modules can be found in many places :

• https://www.orfeo-toolbox.org/CookBook/C++/AddingNewModules.html
• https://wiki.orfeo-toolbox.org/index.php/Remote_Modules
• https://wiki.orfeo-toolbox.org/index.php/How_to_write_a_remote_module
• https://gitlab.orfeo-toolbox.org/orfeotoolbox/otb/-/wikis/Remote-Modules
• https://gitlab.orfeo-toolbox.org/orfeotoolbox/otb/-/blob/develop/CONTRIBUTING.md#remote-modules

Change requested

It would be better to have the documentation about the Remote Modules in one place, well organized, and up to date. I think the CookBook is the best place for this documentation. Other resources should then link to the CookBook page. A table of content could be:

1. Introduction (what are remote modules)
2. Installation of remotes modules (for users who want to use a remote module)
3. Writing a remote module (for user who want to write a remote module)
   1. The steps to make a remote module
   2. Making it official (what to do to add the remote module to https://gitlab.orfeo-toolbox.org/remote_modules)