Added information

[DonutsNL]

1. About how to use namespaces and composer autoloader in Plugins.

2. Maybe add information about future support. Will namespaces be the standard and will /inc be deprecated?

3. I also think it is wise to add the instruction somewhere to "NOT" use existing GLPI classnames inside the plugin namespace or renaming them using: use GlpiPlugins\Namespace\ExistingObjectName as SomethingElse;. I noticed doing so with extends on other existing GLPI objects like CommonDropdown will make the resulting functionality pretty flaky. It should be easy to come up with unique class names.

[DonutsNL]

Forgot to add .vscode to .gitignore obviously xD sorry.

[cconard96]

Just a review of the wording/grammar of the new text.

Also, some of this seems like duplicated information from the other recent PR regarding this change:
#139

[cconard96]

Suggested change

In GLPI 10 and newer installations you are adviced to use namespaces and composer autoloader. Objectfiles using namespaces are no longer loaded by the old autoload.function.php but by the newer Composer autoloader. In order to use the composer autoloader in your plugin must place your classfiles in the `/src` directory instead of the `/inc`. In this scenario the `/inc` directory should no longer be present in the plugin folder structure.

In GLPI 10 and newer installations you are advised to use namespaces and the Composer PSR-4 autoloader. Classes using namespaces are no longer loaded by the old autoload.function.php but by the newer Composer autoloader. In order to use the Composer autoloader in your plugin, must place your PHP class files in the `/src` directory instead of `/inc`. In this scenario the `/inc` directory should no longer be present in the plugin folder structure.

[cconard96]

Suggested change

The the convention to be used is (Case sensitive): `namespace GlpiPlugin\Myplugin;`. The namespace should be added to every classfile in the `/src` directory and should be PHP convention be placed in the top of your classfile. Classfiles using the `GlpiPlugin\Myplugin\` namespaces will be loaded from: `GLPI_ROOT\Plugins\myplugin\src\ClassName.php`. To include folders inside the `/src` directory simply add them to your namespace and use keywords i.e. `namespace GlpiPlugin\Myplugin\SubFolder\` will load `GLPI_ROOT\Plugins\myplugin\src\SubFolder\ClassName.php`.

The convention to be used is (Case sensitive): `namespace GlpiPlugin\Myplugin;`. The namespace should be added to every class in the `/src` directory and per the PSR-12 PHP convention be placed in the top of your class. Classes using the `GlpiPlugin\Myplugin\` namespaces will be loaded from: `GLPI_ROOT\plugins\myplugin\src\`. To include folders inside the `/src` directory simply add them to your namespace and use keywords i.e. `namespace GlpiPlugin\Myplugin\SubFolder\` will load from `GLPI_ROOT\plugins\myplugin\src\SubFolder\`.

[DonutsNL]

You are correct. Documenting this with the folder structure feels like a more natural place. Maybe place a reference back to the plugin structure paragraph somewhere in the 'adding and managing' objects paragraph.

I also tried to make it a bit more verbose for readers to understand whats going on so they are less likely to make typo mistakes and open issues because of this. Sorry for my roughly typed english ;-)