Add GenericObject plugin files and assets

- Introduced default icon images in PNG and SVG formats.
- Added example icons for car and cube in SVG format.
- Created setup file for the GenericObject plugin with versioning and directory definitions.
- Included a header file with licensing information for the plugin.
- Added a remove.txt file with instructions for safe deletion.

plugins/genericobject/composer.json

@@ -0,0 +1,15 @@
+{
+    "require": {
+        "php": "^7.2"
+    },
+    "require-dev": {
+        "glpi-project/tools": "^0.4"
+    },
+    "config": {
+        "optimize-autoloader": true,
+        "platform": {
+            "php": "7.2.0"
+        },
+        "sort-packages": true
+    }
+}